CHEMISTRY AND PHYSICS
DIVE INTEGRATED
Workbook for Assignments and Labs
by David E. Shormann, PhD
Solutions Manual
Digital Interactive Video Education
©2010 Digital Interactive Video Education
©2010 Digital Interactive Video Education
©2010 Digital Interactive Video Education
D.I.V.E. Integrated Chemistry and Physics Workbook for Assignments and Labs Copyright 2008, 2010 Digital Interactive Video Education You are allowed to make 1 copy of this workbook per family member completing this course. ISBN 978-0-9819010-0-8 Published By Digital Interactive Video Education P.O. Box 1324 Magnolia, TX 77353 Printed in the United States of America
©2010 Digital Interactive Video Education
STOP!
Do you have your Reading Syllabus? DIVE Integrated Chemistry and Physics (ICP) has everything you need except a reading supplement. You can supplement your reading using the DIVE ICP Internet Syllabus, or use the reading syllabus that correlates DIVE ICP with your texbook. Go to www.diveintomath.com, click on “Syllabus Index”, and scroll down until you find the Reading Syllabus for your texbook(s), or select the Internet Syllabus. Save it to your computer. If your textbook is not on the list, email me at
[email protected], and I will make a reading syllabus for you! NOTE: Integrated Chemistry and Physics goes by many other names, including Basic Science, Physical Science, and Integrated Physics and Chemistry (IPC). In most states, ICP is worth one high school science credit. We recommend ICP BEFORE a student takes Biology, as many chemistry concepts are covered in the first semester of DIVE Biology. ICP will help prepare a student for these concepts.
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Table of Contents Week # Assignment Laboratory Activity Using DIVE Integrated Chemistry and Physics 1 1-Science, God, and You 1-Laboratory Introduction 2 2-The Scientific Method 2-The Scientific Method 3 3-Units and Unit Analysis 4-Mass, Volume, and Density 3-Measuring Matter 4 5-Scientific Notation and Significant Digits 4-Measuring and Significant Digits 5 6-Solids, Liquids, Gases and the Kinetic Theory 5-Chemical and Physical Changes 6 7-Atoms, Compounds, and Mixtures 6-Elements, Compounds, and Mixt. 7 8-Atomic Structure 7-Electrons and Energy Levels
8 9 10 11 12 13
14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Review for EXAM 1 (Lessons 1-8) Quarterly Exam 1 9-Nuclear Chemistry 8-Nuclear Energy and Radioactivity 10-Periodic Table, Electron Configuration 9-Family Relationships 11-Using the Periodic Table 10-Metals and Nonmetals 12-Chemical Bonding 11-Organic Chemistry, Fractionation 13-Oxidation Numbers, Writing Chemical Formulas 14-Identifying, Writing, and Balancing Chemical Equations 12-Reactions and Equations 15-Solutions 13-Phase Shifts in Solutions 16-Acids, Bases and Salts 14-Acid/Base Titrations Review for EXAM 2 (Lessons 9-16) Quarterly Exam 2 17-Energy and Momentum 15-Newton, Gravity, & Energy 18-Velocity and Acceleration 16-Acceleration 19-Newton's Laws 17-Applications of Newton's Laws 20-Work and Simple Machines 18-Pulleys and 1st Class Levers Bridge Building (see Lab Activity 19) 19-Bridge Building, More Levers 21-Pressure and Fluid Dynamics 20-Press., Buoyancy, and Fluid Force 22-The Gas Laws 21-Boyle's and Charles' Laws Review for EXAM 3 (Lessons 17-22, Labs 15-21) Quarterly Exam 3 23-Thermodynamics 22-Specific Heat of a Metal 24-Static Electricity 23- Static and Current Electricity 25-Current and Ohm's Law 24-Electric Circuits 26-Magnetism and Electricity 25- Mag. Fields and Electromagnets 27-Sound Waves 26-Properties of Sound 28-Electromagnetic Waves 27-Solar power 29-Reflection and Refraction 28-Reflection and Refraction Review for EXAM 4 (Lessons 23-29, Labs 22-28) Quarterly Exam 4 i
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Page ii 1 4 10 17 22 27 31 35 40 44 48 53 58 62 66 71 74 78 83 87 91 97 101 105 110 115 119 125
Using DIVE Integrated Chemistry and Physics (ICP) Using DIVE Science: The goal of DIVE Science is to teach you about God’s creation through reading, lectures, and laboratory activities. At the beginning of each week you should 1)Read the Table of Contents and determine your Assignment(s) 2) Use the Reading Syllabus to find the chapters in your textbook corresponding to the Lesson topics covered and read 3) Complete your definitions using the DIVE ICP Glossary, 4)Watch your lecture(s) and take notes, 5) Complete your Review Questions and grade them, and 6) Complete your Laboratory Activity. DIVE Science is designed to prepare you for college-level work, where note-taking is an important skill. You will take notes on each DIVE lecture, then complete review questions based on the lecture. If you read your book, completed your definitions, and took good notes on the lecture, you should be able to do well on the review questions. Then, every 8 weeks you will have a quarterly exam. Study for this exam by studying your review questions. The DIVE quarterly exams will help prepare you for future college-level exams, which typically cover several weeks of material. Supplies required: A textbook (Bob Jones, Apolgia, or Abeka recommended) or Internet access, DIVE ICP CD (provided), a Reading Syllabus (see instructions on page to left of Contents page), 1 inch 3-ring binder with dividers, college rule notebook paper, 3-hole punch(or 3-hole printer paper), scientific calculator. I recommend that you put the DIVE ICP Workbook in a 3-ring binder, and then add 100 pages of college rule paper (or 3-hole copy paper) for taking notes and writng definitions. Scheduling your year: The Table of Contents is set up as a weekly schedule consisting of Homework Assignment and Laboratory activities. It is designed to be broken up into two, 16-week semesters. I recommend beginning around mid-August, allowing for a break at Thanksgiving, and concluding one to two weeks before Christmas. Continue after New Year’s, taking a week break after the 3rd Quarterly Exam. When you begin a week, first read your table of contents and determine what lesson(s) will be covered. Be flexible! If your child needs an extra week or two in a semester, don’t be afraid to give it to them. Grading: A grading calculator is provided. Watch the Getting Started lesson to familiarize yourself with it.
Notes and definitions (Worth 15%): Grade these based on completion. If your child completed all definitions and took a thorough set of notes, give them a 100%. Deciding what “thorough” means is sometimes difficult. At the very least, briefly review the DIVE Video Lectures assigned for that week, which will give you a good indication of whether your child has a thorough set of notes. Some things your child should take notes on include titles and subtitles, definitions and important concepts, diagrams and tables with notes explaining them, and ALL practice problems. If you have more than one child working on the same DIVE Science course, give the better grade to the one with the more thoroughly completed set of notes.
Review questions (15%): Solutions to review questions are at the end of each DIVE Lecture. A recommended point scale is given on the review questions. Give a percentage grade. For example, if an assignment had 25 total points, and your child missed 4 points, they made a 21 out of 25. Divide 21 by 25, and then multiply this by 100 to convert to a percent (84.0 % in this example). ii
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Using DIVE ICP, continued
Laboratory Assignments (20%): Grade these based on completion. If your child completes all topics covered on the DIVE Video Lab, then give them a 100%. Give lower scores for incomplete, sloppy or lazy work. For most students, lab is their favorite part of science, and lab should be an “easy A” for them. You may find it necessary to set a time limit of 2 hours for lab activities, and if your child has worked hard during that time, give them a 100 even if they don’t complete everything. Quarterly exams (50%). Students who took good notes and studied their definitions and review questions will do the best on exams. Most exam questions will be similar to the DIVE review questions. If your child can correctly answer all the review questions, then they should do fine on the exam. Please note that Exams 3 and 4 will contain questions from the Lab Activities, so please study the labs in addition to the review questions. Exam solutions are provided on the DIVE CD.
Did I pass? Since 1997, I have taught DIVE Integrated Chemistry and Physics to home-educated students in a classroom setting, and based on student grades in those classes, I developed the following grade system for ICP:
91-100 = A 85-91 = B 80-85 = C 75-80 = D Below 75 = F
Sample weekly schedule for ICP: Day 1: Print out DIVE Assignments for the week, read textbook and complete definitions (1-2 hours). Day 2: DIVE assignment (1-3 hrs). Day 3: DIVE assignment (1-3 hrs). Day 4: Complete Lab Assignment (1 to 2 hrs) and any remaining DIVE assignments.
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©2010 Digital Interactive Video Education
Week 1
LESSON 1: SCIENCE, GOD AND YOU
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Data, deductive reasoning, inductive reasoning, observation, science, truth, pure science, applied science, faith, bias, fact 3) Watch the lecture and take notes. 4) Complete review questions, and check answers.
LESSON 1 REVIEW QUESTIONS
Solutions are at the end of the video for this lesson.
1. (4 pts)The statement 2+2 = 4 is called a “defined truth”, because man has defined that statement to be true. List two other defined truths, and two defined “falses”. There are an infinite number of “truths” and “falses”, but here are a few examples Truths: 6-2 = 4 and 7+2 = 9 Falses: 3-1 = 5 and 8+8 = 20 2. (3 pts)Can inductive reasoning be used to prove the following statement: “Whales evolved from cows”? Why? Inductive reasoning can be used to observe what is happening to whales and cows right now, but cannot be used to prove that whales evolved from cows. Inductive reasoning requires human observations, and since no human has ever observed a cow evolving into a whale, then the idea cannot be proved true or false. 3. (1 pt. each)Decide whether each of the following statements is an example of pure or applied science. a. 600 salmon were collected and found to weigh an average of 3.9 kg. pure science b. A certain laser is found to emit only red light. pure science c. Engineers used data that was collected on breaking strengths of various metals to determine which metal would be the best to use for building their bridge. applied science 4. (6 pts)Name three reasons why it is important for Christians to have a good understanding of how the physical universe works. Support each reason with Scripture. There are many reasons you could use here, but make sure that each one you do choose is backed up by a scripture. a) So that you are not deceived by hollow and deceptive philosophies produced by scientists (Colossians 2:8). b) So that you can know God better (Romans 1:20). c) So that you can be a good manager of the natural resources God has given us (Genesis 1:28).
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Week 1
Laboratory Activity
1
Introduction to ICP Laboratory Introduction
Welcome to Integrated Chemistry and Physics (ICP) Laboratory! Reading about science and watching lectures are important parts of any science course, but no science course is complete unless many hours are spent engaged in detailed observation of God's creation through scientific investigations. ICP Laboratory Activities will provide you with an opportunity to test and observe many of the topics covered in the lectures. DIVE ICP Labs will also contain an added emphasis on energy and energy conversion, and we will take a closer look at some of the Christians who discovered important scientific principles, repeating some of the experiments they taught their own students. The laboratory activities in this workbook will be one of two types: observations with data collection, or experiments following the scientific method. In Laboratory Activity 1, you will become familiar with some of the items we will use frequently, including a laboratory burner, a digital balance, and a data logger. We will also discuss some basic laboratory safety.
Methods
Equipment: Laboratory burner, striker, Ohaus digital balance, Xplorer GLX datalogger, weighing dish, sugar. Procedure: For a detailed explanation of the procedure, please watch the video lab. Record all observations in this workbook.
Using a Bunsen burner: Observe the laboratory burner being lit, and answer the following questions. How high above the burner top should you hold the striker? List three things you should never do when lighting a laboratory burner.
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Week 1
Using a Digital Balance:
What is the purpose of the "zero" button?
Weigh 3.00 g of sugar in a weighing dish. What is the weighing dish for?
What are some things you should not do with a balance?
Using a Datalogger:
What is the purpose of a data logger?
Observe the Xplorer GLX datalogger in use. What is the rate of temperature change at t=10s?
_____________________
_____________________
What is the rate of temperature change at t=20s?
Laboratory Safety Material Safety Data Sheets (MSDS) What is the most important section on the MSDS for you to be familiar with?_________________ ___________________________________.
Basic Laboratory Safety
When should goggles be worn?____________________________________________________ ____________________________________________________________________________ How do you mix acid and water?___________________________________________________ Don’t ever_______________ anything, or eat during lab! Your clothes and shoes should_______________________________________________ A very effective method for preventing accidents during lab is to ________________the experiment before performing it.
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Week 2
LESSON 2: THE SCIENTIFIC METHOD
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Scientific method, data, inductive reasoning, deductive reasoning, hypothesis, theory, law, variables, treatment, control, verify 3) Watch the lecture and take notes. 4) Complete review questions, and check answers. LESSON 2 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (2 pts. each) In some science experiments, you are trying to compare the effects that a certain variable may have on the topic of interest. For example, read the following question: What brand of fertilizer makes roses grow the fastest? Let's say you had three brands that you were using, and we will just call them brands A, B, and C. In an experiment, the different types of fertilizer would be called treatments, because you will be treating roses with each type of fertilizer. Most experiments that have a treatment also have a control, which in this case would be roses that had no fertilizer applied to them. In any experiment you want to eliminate as many variables as possible. In this experiment, the only thing you want to vary is the type of fertilizer. Everything else (amount of sunlight, water, soil moisture, temperature, etc.) you hope, will stay the same. Use the information about this example experiment to answer the following questions. A.
How would you come up with a hypothesis for your question? Read what brands claim, ask a nursery that carries all three brands, etc. Make sure that you listed at least two ways to gather enough information to come up with an educated guess.
B.
How many different groups of roses will you have, three or four? 4, three treatments and one control.
C.
Would it be better to use 5 or 50 rose plants in each group? 50 plants. The more that you use, the less chance there is that one “outlier” will significantly effect the average.
D.
What measurement would answer your question better, “final height of plants” or “rate of growth”? Rate of growth, since the question used the word “fastest” and that has to do with the speed or rate.
E. If you were at a science fair and you needed to display your results on a project board, would it be better to average your results for each treatment and make a bar graph, or list all of your raw data in a table? Make a bar graph. If you had 50 plants per treatment, then you would have 200 plants total. Averaging each group leaves you with 4 numbers to display instead of 200, which is much easier to understand. F. If your hypothesis was proven correct by the experiment, what would be the best next step, buy that fertilizer brand for your roses or verify your experiment? Verification would be the best thing to do. G. In describing sources of error for your experiment, do you think it would be more descriptive to list “human error”, or “improper measurement of plant height” as a source of error? NEVER list “human error” as a source of error, because all errors are ultimately caused by humans in an experiment. 4
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Laboratory Activity
2
Week 2
The Scientific Method Introduction
In the early 1600’s, Francis Bacon, considered the founder of the Scientific Method, wrote a two-volume work titled The Advancement of Learning. In order to truly advance learning, Francis believed that “A man cannot be too well studied in the book of God’s word or in the book of God’s works”. He based this idea on Matthew 22:29 when Jesus rebuked the Pharisees because they did not “know the Scriptures or the power of God”. God has commanded us to rule over His creation (Genesis 1:28), but to rule well we need good rules. The scientific method is an excellent tool we can use to reason inductively about His creation. It consists of 5 main parts, which are:
Describe each part of the typical DIVE ICP Laboratory Activity:
Introduction
Hypothesis
Methods
Results
Discussion
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Week 2 The purpose of Laboratory Activity 2 is to use the Scientific Method to answer two different questions. Many of the Laboratory Activities in your DIVE ICP Workbook follow the Scientific Method, and Laboratory Activity 2 is designed to introduce the method to you. You will also become familiar with using Microsoft Excel to organize data, create graphs, and perform statistical analyses.
Part 1: Has the color distribution changed for plain M&Ms? Introduction:
You may be surprised, but M&M candies make excellent tools for learning to organize data and analyze it statistically. M&Ms plain candies have 6 color coatings, and these coatings follow the distribution shown Color red brown yellow green orange blue
Frequency (%) 13 13 14 16 20 24
The "frequency" means that, for example, if you had 100 M&Ms, you would expect 13 of them to be red, 13 brown, 14 yellow, and so on. But is this still the case, or have the manufacturers changed the color frequencies?
Hypothesis: Conduct some research online, or contact the makers of M&Ms directly and ask for "color frequency data" for their plain M&Ms candies (www.mms.com).
Methods
Materials: 100 M&Ms Procedure: Please refer to video lab. Record your data on the following page.
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Week 2 Degrees of Freedom = Color
% observed % expected difference (o-e)2 (o-e)
13 13 14 16 20 24
Red Brown Yellow Green Orange Blue
(o-e)2/e
Σ=
Results: Use the following Chi-Square distribution table to determine whether there was a difference in the expected and observed results. Probability p= 0.05
1 3.84
Chi-square Distribution Table Degrees of Freedom (df) 2 3 4 5.99 7.82 9.49
Discussion
1. Was your hypothesis correct? Why or why not?
2. List at least three sources of error.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment.
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5 11.1
Week 2
Part 2: Does a thermometer's rate of cooling follow a predictable pattern? Introduction:
In Laboratory Activity 1, you observed how temperature changed with time for the temperature sensor on the Xplorer GLX datalogger. We will use the same temperature sensor to answer the question shown.
Hypothesis: Observe the mathematical patterns that Microsoft Excel can predict, and pick one of those.
Methods
Materials: Xplorer GLX Datalogger, temperature sensor, Microsoft Excel. Procedure: Please refer to video lab. Record your data in the following table. Observation #
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time
Temperature
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Week 2
Results:
Use Microsoft Excel to create a trendline for the graph of Temperature (y-axis) versus Time (x-axis)
Equation = _____________________________
R2 = _____________________________
What does R2 tell you?
What is the highest value R2 can attain?
Discussion
1. Was your hypothesis correct? Why or why not?
2. List at least three sources of error.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment.
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Week 3
LESSON 3: UNITS AND UNIT ANALYSIS
Assignment: 1) Read textbook pages corresponding to this topic 2) Define the following terms: Units, metric system, SI, unit multiplier, unit analysis 3) Watch lecture and take notes. 4) Complete review questions, and check answers.
LESSON 3 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. 1-10. Convert the following problems from the given units to the desired units. 1 pt. for correct numerical value, 1 pt. for correct units, 1 pt. for showing your work. (3 pts each) 1)
Convert 600 m to dekameters.
600m
2)
Convert 3 miles to feet.
3 mi
3)
Convert 600 kg to g.
600 kg
4)
Convert 40 cm to μm.
40 cm
5)
Convert 60 m2 to cm2.
60 m2
6)
Convert 60 m3 to cm3.
60 m
7)
Convert 3000 g to lb.
3000 g
(
(
)= 60 dkm
)= 15,840 ft
(
(
( (
3
(
)= 600,000 g )(
)(
)= 400,000 um )= 600,000 cm
2
)= 60,000,000 cm 3
)(
3
)= 6.6 lb 10
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Week 3
8)
Convert 20,000 in. to m.
20,000 in
9)
Convert 20° C to °F. F = 1.8C + 32 F = 1.8(20) + 32 = 680 F
10)
Convert 1 day to seconds.
1 day
(
(
)(
)(
)(
)= 508 m
)= 86,400 s
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Week 3
Table of equivalent measures (memorize these conversions)
Length 12 inches = 1 foot 3 ft. = 1yard 5280 ft. = 1 mile 2.54 cm. = 1 inch 10 mm. = 1 cm. 100 cm. = 1 m. 1000 m. = 1 km. 1.61 km. = 1 mi. Volume 8 oz. = 1 cup 2 cups = 1 pint. 2 pints = 1 quart 4 quarts = 1 gallon 1.057 liter = 1 quart 1000 ml. = 1 liter 1 cm3 = 1 ml. Mass/ Weight 16 oz. = 1 lb. 2000 lb. = 1 ton 2.2 lb. = 1 kg. 1000g = 1 kg. Temperature F = 1.8 C° + 32 K= 273 + C°
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Week 3
LESSON 4: MEASURING MASS, VOLUME, AND DENSITY
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Mass, balance, spring scale, law of mass conservation, weight, Newtons, volume, meniscus, water displacement method, density 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 4 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. 1)
(3 pts) Use unit multipliers to convert 6 lbs. to Newtons.
6 lbs
2)
(3 pts) A rectangular block of concrete has a length of 4 m, a width of 2 m, and a height of 100 cm. Calculate its volume in m3.
4m x 2m x 1m = 8m3
3)
(3 pts) A baseball has a diameter of 7.2 cm. What is its volume in cm3?
(
)= 26.67 N
3
= 195.33 cm3
4)
(3 pts) If the baseball’s mass is 150 g, what is the baseball’s density?
D=
=
= 0.77 g/cm3
5)
(2 pts) Will the baseball sink or float in freshwater? Why?
Float: less dense than water
Use the density tables from the lecture to solve questions 6 and 7. 6) (3 pts) The aluminum can weighed 23 g. What volume of aluminum was used to make the can? 3
(
)= 8.52 cm
23 g
7)
(3 pts) The balloon was filled with 30 liters of helium. How much did this helium weigh? (Hint, convert liters to cm3 first)
30 ℓ
30,000 cm3
8)
(3 pts)Lesson 3 review: Convert 50 m2 to cm2.
50 m2
3
(
(
(
)(
)= 30,000 cm )= 5.4 g
3
3
3
)= 500,000 cm 2
2
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Week 3
Laboratory Activity
3
Measuring Matter Introduction
Matter is defined as anything that takes up space and has mass. Mass is a little more difficult to define, so we will refer to it as the amount of "stuff" something is made of. One of the basic ways that scientists compare different types of matter is to first measure their densities. Density is a quantitative measure of how much space a given mass occupies. If we know an object's mass and volume, we can determine its density by dividing the mass by the volume. Pure water, for example has a density of about 1.0 gram per milliliter (g/mL), which is a common unit used to describe density. In Laboratory Activity 3, you will observe matter and distinguish between mass and weight, and then you will conduct an experiment to determine the density of wood.
Part 1. Mass and Weight In order to better understand the effects of gravity on mass, we will simulate an experiment Michael Faraday performed for some young students in the 1800s (The Forces of Matter by Michael Faraday, p. 12-14). Michael Faraday, also remembered as a humble Christian man, is considered as one of the greatest experimental scientists of all times.
Methods
Procedure: Refer to video lab. Record observations below.
What happened when the acid was added to the soda?
What substance filled the balloon?
How do you know matter went into the balloon?
Describe the difference between mass and weight.
Materials: Digital balance, 250 mL Erlenmeyer Flask, 100 mL graduated cylinder, weighing dish, balloon, spatula, vinegar, baking soda, safety glasses.
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Week 3
Part 2. The density of wood Introduction: Wood is typically less dense than water, and one characteristic of objects that are less dense than water is that they float when placed in water. If an object is less dense than water, then, for a given volume, it has less mass, which means gravity effects it less. If an object is more dense than water, then gravity attracts it more, and it sinks when placed in water. In Part 2 of Laboratory Activity 3, we will answer the following question:
Question: What is the density of wood? Hypothesis: Research wood's density, and come up with an acceptable range of values. If your result lies within this range, then your hypothesis is correct.
Methods
Materials: Digital balance, 100 mL graduated cylinder, ruler or caliper, wooden block Procedure: Refer to video lab. Record observations below.
Mass of wooden block:
Volume 1 by L x W x H:
_______________________g
length = ____________________cm
width = ____________________ cm
height = ____________________cm
volume 1 = ______________________mL
Volume 2 by Water Displacement:
Initial volume of water = ______________mL
Final volume of water = _______________mL
volume 2 = ______________________mL
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Week 3
Results
Density 1 = ________________g/mL
Density 2 = ________________g/mL
Average = _________________g/mL
Helium is often used to fill balloons and make them float. Is helium's ability to rise in air caused because it is unaffected by gravity, or because it is less dense than air?
Discussion:
1. Was your hypothesis correct? Why or why not?
2. List at least three sources of error.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment.
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LESSON 5: SCIENTIFIC NOTATION, SIGNIFICANT DIGITS
Week 4
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Accuracy, precision, scientific notation, significant digits 3) Watch lecture and take notes. 4) Complete review questions, and check answers .
LESSON 5 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. Convert the following numbers from standard form to scientific notation. Don’t round answers. (2 pts each) 1)
23,200 23,200 = 2.32 x 104
2)
356,200,000
356,200,000 = 3.562 x 108
3)
0.0667
6.67 x 10-2
4)
0.000000389 3.89 x 10-7
5) 1.543 1.543 x 100 Convert the following numbers from scientific notation to standard form (2 pts each) 6)
3.63 x 10-2
3.36 10-2= 0.0363
7)
2.55 x 105
255,000
8)
1.389 x 10-5 0.00001389
9)
517.3 x 10-1 51.73
10)
23 x 104 230,000
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Week 4 11)
(2 pts) Three different thermometers were used to measure the temperature of the same cup of water. The graduations on the thermometer were 1° apart. The measurements recorded on the thermometers were 19.5, 20, and 19 degrees Celsius. Would you say these measurements were precise or imprecise.? Why?
12)
(2 pts)The actual temperature of the water was 19.4 °C. Would you say that the thermometers were accurate or inaccurate? Why?
13)
Precise, since they are within 1 graduation of each other.
Accurate: 19.5 ave = 19.4
(2 pts)If the thermometer that was used was a digital thermometer that could measure to the nearest 0.1 °C, would you still say the measurements were precise? Why?
No, I would expect them to be within 0.10C of each other.
14) (2 pts)The digital balance could weigh objects to the nearest 0.01 g. Which would be the appropriate way to record the mass of an object that weighed six grams, 6 g or 6.00 g? Why? 6.00g; record displayed digits
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Week 4
Laboratory Activity
4
Measuring and Significant Digits Introduction
Science is about using the 5 senses God has given us to observe His awesome creation. Sometimes science involves identifying new species, or observing color changes in chemicals. We refer to such observations as "qualitative". At other times, we want to measure lengths, temperatures, volumes, etc., which are referred to as "quantitative" observations. When making quantitative measurements, there is always some error involved. All measuring instruments are built by humans, so they are always subject to some degree of error. Also, many instruments require the scientist to estimate part of the measurement. In Laboratory Activity 4, you will practice making measurements using several devices commonly used in ICP, and you will learn techniques for finding and working with significant digits.
Methods
Materials: caliper, metric ruler, digital balance, digital thermometers (4), identical masses (5), 100 mL graduated cylinder, rectangular eraser, calculator. Procedure: Refer to video lab. Record observations below.
Part 1: Rules for Significant Digits -Multiplication and division: Results of multiplication and division can have no more significant digits than the number with the least number of significant digits in the problem. -Addition and subtraction: The result can have no more significant digits than the number with the lowest place value to the right of the decimal point. -When using an instrument with "graduations", you may estimate one decimal place lower than the place value of the graduations. For example, on a graduated cylinder with graduation marks spaced 1 mL apart, you may estimate to 0.1 mL. -Most of the time, it works if you just do all your calculations out to three or four decimal places, and then go back and look at the numbers that you started with, pick the one with the least number of significant digits, and give your answer that many sig. digits.
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Week 4
Part 2: Making Measurements -Measuring volume with a graduated cylinder.
Record volume: ____________________mL
What place value was estimated? What is the accuracy displayed on the graduated cylinder? Do significant digits affect accuracy or precision?
-Measuring the volume of a rectangular solid with a caliper
length = ____________________cm
width = ____________________ cm
height = ____________________cm
volume = ______________________cm3
-Measuring the length of a book with a metric ruler
length = ____________________cm
How does the caliper increase the accuracy of a measurement?
When should you NOT use significant digits?
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Week 4 -Measuring temperature
Temp. 1 = ____________________°C
Temp. 2 = ____________________°C
Temp. 3 = ____________________°C
Temp. 4 = ____________________°C
Average = ______________________°C
Is the variability a result of the instruments or the substance being measured?
-Measuring mass
Mass 1 = ____________________g
Mass 2 = ____________________g
Mass 3 = ____________________g
Mass 4 = ____________________g
Mass 5 = ____________________g
Average = ______________________g
Is the variability a result of the instrument or the substance being measured?
Calculate the variance in the mass and temperature data. (Variance = average squared deviation of values from the mean)
Which data set showed more variance? 21
©2010 Digital Interactive Video Education
Week 5
LESSON 6: SOLIDS, LIQUIDS, GASES, AND THE KINETIC THEORY
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Physical property, chemical property, chemical change, angstroms, nanometers, atom, kinetic theory, kinetic energy, temperature, absolute zero, kelvin (K), diffusion, Brownian movement, phases, solids, compressibility, amorphouse solids, crystalline solids, liquid, viscosity, gas, gas pressure, plasma, melting, melting point, boiling, boiling point, evaporation, condensation, sublimation, freezing, freezing point 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 6 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-14) (1 pt. each) Fill in the blanks using the following words. Each word should only be used one time.
Absolute, amorphous, boiling, chemical, density, diffusion, evaporation, freezing, gases, liquids, melting, physical, plasmas, temperature 1)
In the engine of a car, gasoline is mixed with oxygen from the air and ignited, forming heat, carbon dioxide chemical and water. This is an example of a _______________________ change.
2)
The water level in the aquarium is lower this week than last week. While fish do drink water, most of the evaporation change in the water level is the result of ___________________.
3)
melting The point at which a solid turns to a liquid is known as the ____________________ point.
4)
boiling The point at which a liquid turns to a gas is known as the ____________________ point.
5)
The air freshener was sprayed in one corner of the room, but could be smelled throughout the room a few diffusion minutes later. This is an example of _______________________.
6)
temperature ______________________ is a measure of the average kinetic energy of particles in a substance.
7)
absolute Most particles stop moving when the temperature reaches ___________________zero.
8)
physical Melting candle wax is an example of a ________________________ change.
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Week 5
9)
density _______________________ is an example of a physical property.
10)
liquids _____________________ can be compressed more than solids, but not as much as gases.
11)
gases ______________ equally distribute themselves inside the container they are in, while liquids take on the shape of their container.
12)
amorphous Crystalline solids have a definite structural shape, while ________________________ solids don’t.
13)
plasmas In gases, particles collide quite forcefully, but in _______________, the particles collide so hard that their structure changes. Examples include neon signs and lightning.
14)
freezing The opposite of melting would be __________________________.
15)
(2 pts) One particle was 37 angstroms in diameter, while the other one was 45 nanometers in diameter. Which one was bigger? (hint, use scientific notation to convert 37 angstroms to nanometers first)
37 x 10-9 45 nanometers = 45 x 10-9 45 nanometers is bigger
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Week 5
Laboratory Activity
5
Chemical and Physical Changes Introduction
A chemical change is a process in which reactants are changed into one or more different products. A chemical change occurs any time a new compound is formed or an existing one is decomposed. During a chemical change, there is a rearrangement of atoms that makes or breaks chemical bonds. This change is usually not reversible, unlike physical changes, which typically are reversible. Chemical changes always result in the formation of new substances, while physical changes never do. Physical changes usually result in a change of shape or state (solid, liquid, gas). A common example of a physical change is the melting of ice, because when ice changes into water, it changes state, but no new substance is formed. Distinguishing between chemical and physical changes can be confusing, and the only way to prove that a chemical change has occurred is to test the new substance. However, there are many observations that give evidence of a chemical change, such as a change in color or temperature, the production of light (flames) or sound, or fizzing (gas production). Usually, when more than one of these processes is observed, than a chemical change has taken place. In Laboratory Activity 5, we will run several different tests, record observations, and formulate hypotheses. We will not attempt to prove the hypotheses with further tests though.
Methods
Materials: Bunsen burner, striker, 250 mL beaker, 10 mL graduated cylinder, aluminum foil, household ammonia, Epsom salt (Magnesium Sulfate), table sugar, baking soda, vinegar, safety glasses. Procedure: Refer to video lab. Record observations below.
Part 1: Make an aluminum foil "spoon" How did the aluminum foil change when you made the spoon?
Based on your observations, hypothesize as to whether a chemical or physical change occurred.
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Week 5
Part 2: Light a Bunsen burner Describe the butane gas before lighting it.
Describe the butane gas after lighting it.
Based on your observations, hypothesize as to whether a chemical or physical change occurred.
Part 3: Heat some sugar. Describe the sugar before burning it.
Describe sugar during and after burning it.
Based on your observations, hypothesize as to whether a chemical or physical change occurred.
Part 4: Mix baking soda and vinegar. Describe the baking soda and vinegar before they were mixed.
Describe the mixture during and after mixing it.
Based on your observations, hypothesize as to whether a chemical or physical change occurred.
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Week 5
Part 5: Mix Epsom salt solution and ammonia. Describe the Epsom salt solution and ammonia before they were mixed.
How do you make a "saturated" solution?
Describe the mixture during and after mixing it.
What is a "precipitate"?
Based on your observations, hypothesize as to whether a chemical or physical change occurred.
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Week 6
LESSON 7: ATOMS, COMPOUNDS, AND MIXTURES
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Atom, element, symbols, molecule, diatomic molecule, compound, molecular formula, pure substances, mixtures, homogenous mixture, heterogeneous mixture, colloids, Tyndall effect, suspension 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 7 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-10) (1 pt. each) Circle the best answer. 1)
Is seawater an example of a homogenous or heterogeneous mixture?
2)
Is N2 a diatomic molecule, compound, or both?
3)
Is CO2 a molecule, compound, or both?
4)
In a suspension/colloid, particles will eventually settle out.
5)
Is a pot of stew an example of a homogenous or heterogeneous mixture?
6)
Is a tank of air an example of a pure substance or a mixture?
7)
Are there two or four oxygen atoms in the compound Mg2SO4?
8)
A solution of salt water is 15% salt by mass. Is the other 85% of the mixture composed of salt or water.?
9)
Is the element symbol for carbon C or Ca?
10)
Is the element symbol for potassium P or K?
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Week 6
Laboratory Activity
6
Elements, Compounds, and Mixtures Introduction
Matter is normally classified into two main groups, pure substances and mixtures. Pure substances include elements and compounds. Elements are substances made of only one type of atom, while compounds are made of two or more different atoms joined by a chemical bond. Mixtures consist of two or more different substances that can be separated by ordinary physical means such as filtering, boiling, centrifuging, or magnetism. Chemists also work with molecules, which are simply two or more atoms joined by a chemical bond. Molecules can be elements (two or more similar atoms) or compounds (two or more different atoms). Therefore, molecules can be compounds, but compounds cannot be molecules because they must have two or more different atoms bonded together. Many people mistakenly call molecules like H2 and N2 "compounds". In Laboratory Activity 6, you will become familiar with several elements and compounds, and you will use physical processes to separate a mixture.
Part 1: Elements and compounds Methods
Materials: Iron filings (Fe), table salt (NaCl), Epsom Salt (MgSO4), Cupric Sulfate (CuSO4•5H2O), Baking Soda (NaHCO3), Sulfur (S), Zinc (Zn), Aluminum (Al), Calcium (Ca), Copper (Cu), Magnesium (Mg), Mercury (Hg), Sodium (Na), Lead (Pb), Iodine(I2), Carbon as graphite (C), Vinegar, spatula, weighing dishes, distilled water, safety glasses. Procedure: Refer to video lab. Record observations below. DO NOT MIX ANY OF THE CHEMICALS!
Compare and contrast several elements and compounds, and record your observations in the table on the following page.
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©2010 Digital Interactive Video Education
Week 6 Substance
Chemical Formula
Zinc
Formula Specific weight Gravity 65.41
Aluminum
26.98
Copper
63.55
8.96
Iron
55.85
7.87
Calcium
40.08
Sulfur
32.06
Graphite
12.01
Mercury
200.6
Magnesium
24.3
Sodium
22.99
Lead
207.2
11.3
Iodine
126.9
4.93
Table Salt
58.44
2.17
Cupric Sulfate
2.07
13.53
2.29
Baking Soda
84.0
Mercuric Chloride Epsom Salt Vinegar
Description
2.20 5.6
C2H4O2
246.4
1.67
60.0
1.01
Which substance was the most dense? Which substance would float in water? What is the difference between a molecule and a compound?
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Element or Compound?
Week 6
Part 2. Separating a Mixture Introduction: Iron (Fe) an element, and table salt (NaCl), do not spontaneously react when mixed together at room temperature. Therefore, if a mixture is made of the two, then they should still be separable by ordinary physical processes.
Question: Can a mixture of iron and salt be separated? Hypothesis: Read the introduction and develop a hypothesis.
Methods
Materials: Bunsen burner, striker, iron ring, ring stand, wire gauze, clay triangle, 100 mL beaker (2), funnel, filter paper, bar magnet, glass stir rod, iron filings (Fe), table salt (NaCl), safety glasses. Procedure: Refer to video lab. Record observations below.
Describe the appearance of the mixture:
Results
Were you able to separate the salt and iron?
Discussion:
1. Was your hypothesis correct? Why or why not?
2. What was the main source of error?
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment.
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Week 7
LESSON 8: ATOMIC STRUCTURE
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Law of definite proportions, electrons, nucleus, protons, neutrons, energy levels, quantum model, orbitals 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 8 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-5) (1 pt. each) Circle the best answer.
1)
Electrons have a ______________ charge a) positive
2)
Protons have a ______________ charge a) positive
3)
_______________ determined that different elements have different masses. b)Democritus c)Rutherford d)Thomson e)Bohr
4)
___________________ discovered electrons. a) Dalton d)Thomson e)Bohr
5)
Prior to the quantum model, the atomic model developed by ______________ was the most sophisticated model. a) Dalton b) Democritus c) Rutherford d) Thomson e) Bohr
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b) negative b) negative
c) neutral c) neutral
b)Democritus
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a) Dalton c)Rutherford
Week 7
Laboratory Activity
7
Electrons and Energy Levels Introduction
In the early 1900’s, Neils Bohr developed his theory of atomic energy levels. It was based on ideas he gathered from James Jeans’ experiments with radiant energy. Jeans found that radiant energy could exist only in certain minimum amounts or multiples thereof, so Bohr applied that idea to electrons orbiting atoms. An atom’s electrons could be thought of like a bicycle’s gear system. On a bicycle, you can ride in 1st, 2nd, 3rd gear, etc., but not in between gears. Likewise on an atom, electrons exist in distinct energy levels around an atom, and when an atom “falls” from a higher to a lower energy level, the lost energy is released in the form of light energy. Since the electron fell a distinct, or “quantized” amount, then it gives off a distinct color (or wavelength of light). Therefore, since each atom is different with different numbers of electrons and energy levels, when energy is added, each atom will release that energy in a different way with different colors. In Laboratory Activity 7 you will answer the question:
Can the color of radiant energy released by atoms be used to predict an unknown element? Hypothesis: (read Introduction) Methods
Materials: Equipment: Bunsen burner, striker, spatula, XPlorer GLX Datalogger, Ocean Optics Spectrometer, 150 mL beaker, wooden splints, safety glasses Chemicals: distilled water, chloride salts of calcium, copper, lithium, manganese, potassium, sodium, and strontium Procedure: Refer to video lab. Record observations below.
Element
Color(s) observed
Copper
Potassium Strontium Lithium Manganese Calcium Sodium Unknown 32
©2010 Digital Interactive Video Education
Week 7 Sketch the spectra for copper and sodium on the graphs below: COPPER
380-420 420-440 440-500 500-520 520-565 565-590 590-625 wavelengths in nanometers
625-740
SODIUM
380-420 420-440 440-500 500-520 520-565 565-590 590-625 wavelengths in nanometers
625-740
Results
What was the unknown element?
Did the copper and sodium spectra reveal distinct bands of light in the colors you expected?
Discussion:
1. Was your hypothesis correct? Why or why not?
2. List 3 sources of error.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment.
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Week 8
Week 8 STUDY FOR
QUARTERLY EXAM 1 COVERS LESSONS 1-8
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©2010 Digital Interactive Video Education
LESSON 9: NUCLEAR CHEMISTRY
Week 9
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Atomic mass, atomic mass unit, atomic number, mass number, isotopes, isotopic notation, nuclear chemistry, radioactivity, alpha particle, beta particle, gamma ray, alpha decay, beta decay, radioactive dating, nuclear bombardment reaction, nuclear fission, chain reaction, theory of relativity, nuclear fusion 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 9 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-10) (1 pt. each) Fill in the blanks using the following words. Each word should only be used one time. Alpha, electron, fission, four, fusion, gamma, isotopes, nucleus, number, eight
gamma 1) A ___________________ ray is a high energy electromagnetic wave. electron 2) A beta particle forms when one neutron disintegrates into one proton and one _______________________. 3) An isotope of carbon has an atomic mass number of 14, and an atomic number of 6. This carbon has eight ____________________ neutrons.
alpha 4) ______________________ radiation has the weakest penetrating power. number 5) The atomic _______________________ equals the number of protons in the nucleus of an atom. isotopes 6) ____________________ of an atom have the same number of protons but a different number of neutrons. 7) During alpha decay, an atom emits a helium_________________________. nucleus
fusion 8) Nuclear ___________________ is carried on by the sun. fission 9) Nuclear power plants operate off of a controlled chain reaction produced by the ______________________of radioactive materials. four 10) An alpha particle has a mass number of ________________________.
11) Lesson 3 review. Convert 6 meters to inches.
(
6m
)(
)=
= 236.22 in
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©2010 Digital Interactive Video Education
Week 9
Laboratory Activity
8
Nuclear Energy and Radioactivity Introduction The first nuclear power plant to generate electricity was in 1951 at the EBR-I experimental station near Arco, Idaho (http://en.wikipedia.org/wiki/Nuclear_power). Compared to the thousands of years that man has utilized various sources of energy, our understanding of nuclear energy is just beginning. Humans have learned the tremendous benefits of harnessing the energy released from the fission of Uranium, but we have also learned the tremendous dangers involved. The following diagram, copied with permission from www.stpnoc.com, shows the general layout of a nuclear power plant. Inside the reactor, neutrons bombard uranium pellets, splitting the uranium and releasing more neutrons and heat energy. A chain reaction ensues, and the reactor is designed to keep this chain reaction under control. If the reactor loses control of the fission process, a “meltdown” can occur, destroying the power plant and possibly contaminating the area with radiation.
Fortunately, great advances have been made in controlling nuclear reactors and storing radioactive waste, and nuclear reactors are now one of the safest and cleanest forms of energy available. In Laboratory Activity 8, you will compare nuclear and coal power, and make observations and draw conclusions regarding radioactive decay and radioactive waste. 36
©2010 Digital Interactive Video Education
Week 9
Part 1: Comparing Electricity generated from Nuclear and Coal Power Methods: Equipment: Calculator Procedure: Answer the following questions. You will need the following information to help you answer the questions*: 1 kilowatt-hour (kWh) = 3.6 x 106 Joules 1 short ton = 2000 lbs 1 metric ton=1000 kg Speed of sound = 3.00 x 108 meters per second Amount of coal used in electricity production in the United States in 2006 = 1,026,636,000 short tons Electricity produced from 1 ton of coal =1 Uranium fuel pellet = 1.08 x 1010 Joules Electricity produced by nuclear power in the United States, 2006 = 7.87 x 1011 kWh *Estimates are from various sources, including en.wikipedia.org, www.eia.doe.gov and stpnoc.com. 1) Use E=mc2 to estimate the mass in kilograms of Uranium in 1 fuel pellet.
2) How many Uranium fuel pellets were used for electricity production in the United States in 2006? What mass (in kilograms) of Uranium is this?
3) What mass (in kilograms) of coal was used in the United States in 2006 for electricity production?
4) How much electricity (in kWh) was produced using coal in the United States in 2006?
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Week 9 5) In 2006, what was the coal:nuclear electrical energy production ratio?
6) What is the biggest limiting factor in using coal or uranium for nuclear power?
Part 2: Simulating Radioactive Decay Methods: Equipment: 40 pennies Procedure: Refer to video lab. Record data below. "Time"
Number of pennies
Number of pennies
0 1 2 3 4 5 6 7 8
40 30 20 10 0 0
2 4 6 8 "Time"=Number of half lives
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©2010 Digital Interactive Video Education
10
Week 9 What is radioactive half-life?
Does radioactive decay follow a linear or non-linear pattern? What concerns does this pattern raise for radioactive waste from nuclear power plants?
Part 3: Storage of Radioactive Wastes In 2008, the U.S. Department of Energy (DOE) announced submittal of a license application (LA) to the U.S. Nuclear Regulatory Commission (NRC) seeking authorization to construct America’s first repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain, Nevada. The 8,600 page application describes DOE’s plan to safely isolate spent nuclear fuel and high-level radioactive waste in tunnels deep underground at Yucca Mountain, a remote ridge on federally controlled land in the Mojave Desert 90 miles northwest of Las Vegas. Currently, the waste is stored at 121 temporary locations in 39 states across the nation. Watch excerpts from a video on the construction of the Yucca Mountain Facility (www.ymp.gov), and answer the questions below. What is the purpose of the Yucca Mountain Facility? Why is it located underground in the desert?
What is the main concern of storing radioactive waste in this facility?
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©2010 Digital Interactive Video Education
Week 10
LESSON 10: PERIODIC TABLE, ELECTRON CONFIGURATION
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Periodic table, periodic law, electron configuration, valence electrons 3) Watch lecture and take notes. 4) Complete review questions, and check answers.
LESSON 10 REVIEW QUESTIONS Solutions are at the end of the video for this lesson.
1) (3 pts) Why is the table of the elements called a “periodic” table? Start your answer by defining the word periodic. Periodic means "repeating patter". Since the chemical and physical properties of elements have a repeating pattern, the table that lists the elements is called a periodic table.
Questions 2-5: Determine the electron configuration of the following elements. Atomic numbers for each element are in parentheses. One point for each correctly worked level. 2)
Oxygen (8)
2 Level 1______ 3)
Level 4______
2 Level 2______
Level 3______
Level 4______
5 Level 3______
Level 4______
18 Level 3______
7 Level 4______
Phosphorous (15)
2 Level 1______ 5)
Level 3______
Lithium (3)
2 Level 1______ 4)
6 Level 2______
8 Level 2______
Bromine (35)
2 Level 1______
8 Level 2______
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©2010 Digital Interactive Video Education
Laboratory Activity
9
Week 10
Family Relationships Introduction Vertical columns of the periodic table are often referred to as families, the main reason being that the chemicals behave in similar ways, especially the "Group A" elements. Typically, the members of a Group A family all have the same number of valence electrons, which also corresponds to their Group Number. For example, Group 1A elements all have 1 valence electron, Group 2A elements all have 2 valence electrons, etc. In Laboratory Activity 9, you will study some of the elements within a group and draw conclusions about the behavior of the other elements in that group.
Part 1: Predicting Chemical Formulas Methods Materials: Periodic Table that displays Group A elements (See Lab 10). Procedure: Record data below. Group 1A and 7A elements: Sodium (Na) and Chlorine (Cl) combine to form Sodium Chloride (NaCl). Use this information to predict the chemical formulas that result when Potassium (K) combines with Cl, Br, and I.
Group 2A and 7A elements: Magnesium (Mg) and Chlorine (Cl) combine to form Magnesium Chloride (MgCl2). Use this information to predict the chemical formulas that result when Calcium (Ca) combines with F, Cl, and Br.
Part 2: Predicting the Behavior of Group 1A elements. Question: Is it possible to predict the behavior of Potassium by observing other Group 1A elements? Hypothesis: Read introduction, textbook or internet to develop your hypothesis.
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Week 10 Methods:
Materials: 50 mL Erlenmyer flask, balloon, 100 mL graduated cylinder, 250 mL beaker, Aluminum pellets or foil, Sodium (Na), Potassium (K), Hydrochloric Acid (HCl), lighter, oven mitt, ice water bath, water, safety glasses.
Procedure: Due to the hazardous nature of this activity, it is recommended that you not attempt it on your own. Record observations in the area below.
Hydrogen Describe its appearance:
What happened when it reacted with oxygen?
Sodium Describe its appearance:
What happened when it was placed in water?
Potassium
Describe its appearance:
PREDICT what will happen when placed in water.
Results
What happened when the Potassium was placed in water?
Did the Potassium seem more or less reactive than Sodium? Why would this be?
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Week 10
Discussion:
1. Was your hypothesis correct? Why or why not?
2. List 3 sources of error.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment.
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©2010 Digital Interactive Video Education
Week 11
LESSON 11: USING THE PERIODIC TABLE
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Family, group, alkali metals, alkaline-earth metals, alloys, transition elements, halogens, transuranium elements, noble gases, periods, series, metals, luster, malleable, ductile, metalloids, nonmetals 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 11 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-10) (1 pt. each) Fill in the blanks using the following words. Each word should only be used one time. Alkali, alkaline-earth, carbon, families, halogens, metalloids, periods, series, six, three 1)
metalloids Since _________________ are slightly conductive, they are referred to as semiconductors.
2)
Vertical columns of the periodical table contain elements that have similar properties. The columns are also families known as ____________________, or groups.
3)
series Elements located in the same _______________ have their valence electrons in the same outermost energy level.
4)
three Boron is in group 3A, so it has __________________ valence electrons.
5)
periods Horizontal rows of the periodic table are called ___________________, or series.
6)
halogens The _____________________ are a group of very reactive nonmetals, while the noble gases are very inert nonmetals.
7)
six Sulfur is in group 6A, so it has ___________________ valence electrons.
8)
carbon Group 4A is also known as the __________________ family.
9)
alkali Potassium is an example of an __________________ metal.
10)
alkaline-earth Ca is an example of an ________________________ metal.
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Laboratory Activity
Week 11
10
Metals and Nonmetals Then Simon Peter, having a sword, drew it and struck the high priest's servant, and cut off his right ear. The servant's name was Malchus. So Jesus said to Peter, "Put your sword into the sheath. Shall I not drink the cup which my Father has given me?" John 18: 10-11
Introduction All elements can either be classified as metals or nonmetals. Most of the elements are metals. The nonmetals also include the metalloids and the noble gases. Metals are either solid or liquid, and are typically shiny. Sometimes the surface of metals becomes oxidized, giving them a dull appearance, but if they are cut to expose the inner layers, their "metallic" shine is observed. Metals are also very conductive to electricity, while nonmetals are not, although there are a few exceptions. In Laboratory Activity 10, you will learn about metals and nonmetals, and classify some elements as either metals or nonmetals. 1A 1 H
Metals Nonmetals Metalloids Noble gases
2A
3 Li
4 Be
11 Na
12 Mg
3B
4B
5B
6B
7B
19 K
20 Ca
21 Se
22 Ti
23 V
24 Cr
25 26 Mn Fe
37 Rb
38 Sr
39 Y
40 Zr
41 42 43 Nb Mo Tc
55 Cs
56 Ba
57-71
72 Hf
73 Ta
74 W
75 Re
87 Fr
88 Ra
89-103 Ac-Lr
58 Ce
59 Pr
90 Th
91 Pa
La-Lu
--------8B----------- 1B
2B
8A 2 He
3A
4A 5A
6A
7A
5 B
6 C
7 N
8 O
9 F
10 Ne
13 Al
14 Si
15 P
16 S
17 Cl
18 Ar
27 Co
28 Ni
29 Cu
30 Zn
31 Ga
32 Ge
33 As
34 Se
35 Br
36 Kr
44 Ru
45 Rh
46 Pd
47 Ag
48 Cd
49 In
50 Sn
51 Sb
52 Te
53 I
54 Xe
76 Os
77 Ir
78 Pt
79 Au
80 Hg
81 Tl
82 Pb
83 Bi
84 Po
85 At
86 Rn
60 61 62 63 Nd Pm Sm Eu
64 65 Gd Tb
66 Dy
67 68 Ho Er
69 70 Tm Yb
71 Lu
92 U
96 97 Cm Bk
98 Cf
99 Es
93 94 Np Pu
95
Am
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©2010 Digital Interactive Video Education
100 101 102 103 Fm Md No Lr
Week 11
Part 1: Getting to know the metals and nonmetals Methods Materials: Periodic Table, Bible. Procedure: Record data below.
-Make a list of all the metals on the Periodic Table on page 45 (element symbols only) Li, Be, Na, Mg, Al, K, Ca, Se, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Mo, Te, Ru, Pd, Ag, Cd, In, Sn, Cs, Ba, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Pb, Bi, Bi, Fr, Ra, Th, Pa, U, Np, Pu, Am, Cm, Bk, Cf, Es, Fm, Md, No, Lr
-Make a list of all the nonmetals on the Periodic Table on page 45 (element symbols only)
H, He, B, C, N, O, F, Ne, Si, P, S, Cl, Ar, Ge, As, Se, Br, Kr, Sb, Te, I, Xe, Po, At, Rn
-List 5 Bible verses referring to metals or the use of metals.
John 18:10-11, Proverbs 27:17, Daniel 2:33, Daniel 2:39, Numbers 21:9
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©2010 Digital Interactive Video Education
Week 11
Part 2: Classifying Elements In Part 2, you will observe several elements, measure their conductivity, predict whether they are metals or nonmetals, and then determine if your prediction matches the Periodic Table classification.
Methods Materials: Digital Multimeter, Aluminum, Bismuth, Carbon (bituminous coal), Carbon (graphite powder), Carbon (pencil "lead"), Copper (wire), Iron (nail), Magnesium, Silicon, Sulfur Procedure: Record observation below. Substance
Description
Is it Conductive?
Aluminum Bismuth Coal Graphite Pencil Copper Iron Magnesium Silicon
- Sulfur
Which predictions did not match the Periodic Table's classification? Explain why.
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Metal or Nonmetal (prediction)
Metal or Nonmetal (periodic table)
Week 12
LESSON 12: CHEMICAL BONDING
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Electronegativity, ionic bond, ion, anion, cation, electron dot structure, crystal lattice, formula unit, electrolyte, covalent bond, diatomic molecule, polyatomic molecule, metallic bond, free electron theory 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 12 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-10) (1 pt. each) Circle the correct answer. 1)
This type of bond forms cations
a)ionic
b)covalent
c) metallic
2)
This type of bond forms compounds that are conductive when dissolved in water c) metallic
3)
This type of bond forms only between nonmetals
4)
In this type of bond, the electrons are free to move
5)
In this type of bond, the electrons are transferred
6)
This type of bond will form between elements with similar, low electronegativities c) metallic
a)ionic b)covalent
7)
This type of bond will form between elements with similar, high electronegativities c) metallic
a)ionic b)covalent
8)
This type of bond may form solids with low melting points
9)
When dissolved in water, substances containing this type of bond form electrolytes. c) metallic
10)
Diatomic molecules are usually formed from this type of bond.
a)ionic
b)covalent
a)ionic a)ionic
b)covalent b)covalent
a)ionic
11) Ca
12) Si
13) O
14) Br
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c) metallic c) metallic c) metallic
b)covalent
a)ionic
Draw the electron dot structure for the following atoms. (2 pts. each).
a)ionic b)covalent
c) metallic a)ionic b)covalent
b)covalent
c) metallic
Laboratory Activity
11
Week 12
Organic Chemistry and Fractionation Introduction
Organic Chemistry is a discipline within chemistry involving the study of compounds consisting primarily of carbon and hydrogen. The original definition of "organic" chemistry came from the misconception that organic compounds were all from living organisms. However, organic molecules can be produced by processes not involving life. The majority of organic compounds consist of covalently bonded materials, although some form ionic bonds. Millions of organic compounds exist, and scientists have come up with unique ways to organize and classify them. In Laboratory Activity 11, you will learn some of the basics of identifying and naming organic compounds, and you will learn a technique called fractionation, which is frequently used to separate mixtures of organic compounds based on differences in boiling points.
Part 1: Naming Organic Compounds Methods
Materials: none
Hydrocarbons:
What are hydrocarbons?
Procedure: Refer to video lab. Record data below.
What are alkanes?
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Complete the Chart: Prefix meth-
Number of Carbons 1
eth-
2
prop-
3
but-
4
pent-
5
hex-
6
hept-
7
oct-
8
non-
9
dec-
10
Alkane name
Structure
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Functional Groups:
Observe the functional groups, and then identify what functional group each of the following compounds contains.
alcohol
Acetone, CH3COCH3 is a/an alcohol, ketone, aldehyde or amine?
Ethanol, CH3CH2OH, is a/an alcohol, ketone, aldehyde or amine?
Formaldehyde, CH2O is a/an alcohol, ketone, aldehyde or amine?
Part 2: Fractionation
Can acetone be separated from a mixture of water and acetone?
Hypothesis: research the boiling points of water and acetone.
ketone
aldehyde
amine
As mentioned previously, fractionation, and more specifically fractional distillation, is frequently used to separate mixtures of organic compounds based on differences in boiling points. If you have ever seen a petroleum refinery, the tall columns you see are fractionation towers used to separate hydrocarbons and other compounds from the crude oil mixture. In Part 2 of Laboratory Activity 11, you will answer the following question:
Methods: Materials: Digital balance, Xplorer GLX Datalogger and temperature sensor, 50 mL distillation flask, sidearm test tube, #2 rubber stopper (2), 400 mL beaker, 10 mL graduated cylinder, pipet, ring stand, iron ring, test tube clamp (a.k.a. burette clamp), boiling chips, Bunsen burner, striker, acetone, ice, distilled water, safety glasses. Procedure: Record data on following page. 51
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Week 12
Initial:
volume of acetone:____________mL boiling pt of solution:______________°C
Final:
mass of acetone:_________g
mass of acetone:_________g
volume of acetone:____________mL boiling pt of solution:______________°C
Results: Calculuate initial and final densities of acetone, and % difference ((L-S)/L)100%
initial density:____________g/mL
final density:____________g/mL
% difference_____________%
Discussion:
1. Was your hypothesis correct (% difference ≤ 5%)? Why or why not?
2. List at least three sources of error.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment.
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Week 13
LESSON 13: OXIDATION NUMBERS, WRITING CHEMICAL FORMULAS
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Chemical formula, subscripts, oxidation numbers, polyatomic ions, binary compounds 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 13 REVIEW QUESTIONS Solutions are at the end of the video for this lesson.
The chemical formulas shown in problems 1 through 5 are incorrect. Use what you know about oxidation numbers to write the correct formula. Use the oxidation numbers from the chart shown during lecture for your oxidation numbers. Assume all compounds are neutrally charged. (2 pts each.) +2 -1
1)
CaCl CaCl2
2)
HO
3)
LiF2 LiF
4)
FeO Assume Fe has an oxidation number of +3. +3 -2 Fe2Cl3 CH3
5)
+1 -2
H2O +1 -1
-4 +1
CH4 6)
Write the chemical formula of the compound that would form from the reaction of potassium and nitrate. (2 pts.) KNO3
7)
Write the chemical formula of the compound that would form from the reaction of hydrogen and phosphate. (2 pts.) H3PO4
For problems 8-12, write the name of the compound that would form from the reaction of the chemicals shown. Only use prefixes such as tri, di, etc., on problem 10. (2 pts each) 8) Ca and F 9) Mg and OH-
10)
12)
calcium fluoride
Sodium sulfide
Fe (II) and O, and Fe(III) and O
11)
Na and S(II)
magnesium hydroxide
Potassium sulfate
K and SO42-
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Week 13
LESSON 14: IDENTIFYING, WRITING, AND BALANCING CHEMICAL EQUATIONS Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Chemical equation, reactants, products, coefficients, combination reaction, decomposition reaction, electrolysis, single-replacement reaction, double replacement reaction, precipitate, endothermic reaction, exothermic reaction. 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 14 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. Problems 1-3. Write down next to each equation whether you think it is a single replacement, double replacement, composition, or decomposition reaction (1 pt. each). 1)
2Cu + O2 →
2)
Na2SO4
3)
Ca
2CuO
composition
+ 2KNO3 →
K2SO4 +
double replacement
+ 2HCl
→
CaCl2
2NaNO3
+ H2
single replacement
In Questions 4-10, determine if the equation is balanced or not. If it is not balanced, then balance it. (3 pts. each) 4)
H2 + I2 → HI
5)
H2 + I2 → 2 HI
NOBr →
2NO + Br2
2 NOBr → 2NO + Br2
6)
→
2ClO
7)
8)
→
O2
4 NO2 CO2 →
+ +
O2 H2O
CO2
+ 2 H2O
C2H6
Balanced
H3O+ + OH- →
+
2 O2 + CH4
H2 +C2H4 →
10)
2NO2
2N2O5 →
O2 + CH4
9)
Balanced
2N2O5 →
Cl2 + O2
H2O
H3O+ + OH- → 2 H2O
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Laboratory Activity
12
Week 13
Reactions and Equations Introduction
In Laboratory Activity 12, you will practice writing and balancing chemical equations, and you will classify several types of reactions.
Methods
Materials: Digital balance, Ring stand, iron ring, wire gauze (2), Bunsen burner, sparker, crucible tongs (or pliers), test tubes (4), test tube rack, 250 and 100 mL beakers, 9V battery, spatula, Zinc powder (Zn), Sulfur (S), 1 M Copper Sulfate (CuSO4•5H2O), 0.5 M Lead Nitrate (Pb(NO3)2), 0.5 M Potassium Chromate (K2CrO4), 0.1 M Potassium Hydroxide (KOH), Magnesium ribbon, distilled water, weighing dishes, oven mitt, matches, safety glasses. Procedure: Refer to video lab. Record data below.
Zinc and Sulfur.
Describe the Zinc and Sulfur before and after mixing:
Zinc: Dull gray fine powder
Sulfur: Flat yellow powder
Mixture: Light gray powder
What happened when the flaming magnesium was added to the Zinc/Sulfur mixture? Describe the final product. A small explosion occurred, producing flames, sparks, and smoke. The final product was a yellow and white solid.
Write a balanced chemical equation for the reaction.
Zn + S → ZnS
Circle the type of reaction: Composition, decomposition, single replacement, double replacement
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Zinc and Copper Sulfate.
Describe the Zinc and Copper Sulfate before mixing:
Zinc: Dull, gray fine power
Copper Sulfate: Clear blue liquid
What happened when the Zinc was added to the Copper Sulfate and mixed? Describe the final solution and solid. The solution lost most of its blue color and the Zinc turned black/brown.
Write a balanced chemical equation for the reaction.
Zn (s) + CuSO4 (aq) → Cu (s) + ZnSO4 (aq)
Circle the type of reaction: Composition, decomposition, single replacement, double replacement
Lead Nitrate (Pb(NO3)2) and Potassium Chromate (K2CrO4).
Describe the Lead Nitrate and Potassium Chromate before mixing:
Lead Nitrate:
Potassium Chromate: Clear orange solution
What happened when the Lead Nitrate and Potassium Chromate mixed? Describe the final solution and solid. A bright yellow precipitate and clear liquid formed
White, opaque solution
Write a balanced chemical equation for the reaction.
Pb(NO3)2 (aq) + K2CrO4 (aq) →
PbCrO4 (s) + 2KNO3 (aq)
Circle the type of reaction: Composition, decomposition, single replacement, double replacement
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The electrolysis of water.
What is electrolysis? The splitting (lysis) of a compound using electricity (electrons)
What gases does electrolysis break water (H2O) into? Hydrogen (H2) and Oxygen (O2)
One test tube has more gas than the other, what gas is this? How do you know? Give two reasons. Hydrogen, because water has twice as much hydrogen as oxygen, and because it exploded when lit with a match.
How does Potassium Hydroxide act as a catalyst in the electrolysis reaction? The Potassium and Hydroxide ions provide a pathway for the transfer of electrons from one electrode to the other.
Write a balanced chemical equation for the reaction. 2H2O (l) → 2H2 (g) + O2 (g)
Circle the type of reaction: Composition, decomposition, single replacement, double replacement
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Week 14
LESSON 15: SOLUTIONS
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Solution, solute, solvent, suspension, amalgam, alloys, dipole, polar molecule, dissociation, soluble, solubility, miscibility, precipitate, saturated, supersaturated, insoluble, Henry’s law, percentage by mass, specific gravity, boiling point elevation, freezing point depression 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 15 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-10) (1 pt. each) Fill in the blanks using the following words. Each word should only be used one time. Dissociate, Henry’s law, immiscible, lower, nonpolar, precipitate, saturated, solute, 36, 210 1)
solute The substance being dissolved is the _____________________ .
2)
saturated When no more substance will dissolve, the solution is said to be _____________________.
3)
When no more of a solid will dissolve in a liquid, any more additions of the solid will cause a precipitate ____________________________ to form.
4)
immiscible Two liquids that will not dissolve when mixed are called _________________________ liquids.
5)
36 At 25° C, _____________grams of sodium chloride will dissolve in 100 ml of water.
6)
210 At 25° C, ______________ grams of table sugar will dissolve in 100 ml of water.
7)
nonpolar Polar molecules usually won’t dissolve in _______________________ solvents.
8)
dissociate When table salt dissolves in water, the sodium and chloride ions __________________________.
9)
Packaging carbonated beverages under pressures higher than atmospheric pressure is an application of Henry's law _________________________.
10)
lower Salt is placed on icy roads in an effort to ________________________ the freezing point of water.
11)
What is the percent by mass of 23 g of sucrose dissolved in 77 g of water? (3 pts.)
12)
13)
=
x 100% = 23%
How much salt is in 300 g of a 3.5 % solution of salt water? (3 pts)
x 300 g soln. = 10.5 g salt
Ice has a specific gravity of 0.92. Will it float or sink in fresh water? (2 pts)
Float, less dense
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Laboratory Activity
13
Week 14
Phase Shifts in Solutions Now there were set there six waterpots of stone, according to the manner of purification of the Jews, containing twenty or thirty gallons apiece. Jesus said to them, "Fill the waterpots with water." And they filled them up to the brim. And He said to them, "Draw some out now, and take it to the master of the feast." John 2:6-8
Introduction
John 2 describes how Jesus turned water into wine at a wedding feast. While only God could transform water in such an incredible and miraculous way, in Laboratory Activity 13 we will transform water in some pretty interesting ways by raising its boiling point and lowering its freezing point. First though, we will learn more about solutions and units used for concentration.
Part 1: Units used for concentration
Materials: Calculator, Periodic Table with Atomic Masses Procedure: Refer to video lab. Record data below.
Parts per "
".
Percent -Percent by mass is the same thing as parts per _________________.
-How many grams of water are needed to make a 20% Potassium Chloride solution?
Parts Per Thousand
-The average seawater salinity is 35‰. If you had 1000 lbs of seawater, how many lbs of salt would it contain?
-Describe how you would make 100 mL of a 35‰ salt solution.
Dissolve 35 g NaCL in 965 mL of distilled water, and then pour a 100 mL sample.
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Parts Per Million -Most animals cannot survive in water containing less than 2 ppm dissolved oxygen. If you had a million pounds of seawater at the point of hypoxia, how much oxygen would it contain?
-Convert 2 ppm O2 to mg/L
Molarity
-1 Mole = _______________________________ things.
-This number is known as _______________________ number.
-Atomic mass is the mass of _________________ of an element.
-Formula weight is the mass of ___________________ of a compound.
-What is the formula weight of NaCl?
-What is the formula weight of KNO3?
-Molarity (M) is the number of _________________ of solute dissolved in 1 Liter of solvent.
-Describe how to make 1 Liter of a 0.5 M solution of NaCl. Dissolve 29.22 g (0.5 M) of NaCl in 1 L of distilled water.
Part 2: Phase shifts in solutions In Part 2, you will learn about colligative properties of solutions. Colligative properties are properties of solutions that depend only on the number of solute particles dissolved in a given volume of solvent. Colligative properties include the lowering of a solution's freezing point and the raising of its boiling point. In Part 2, you will study colligative properties of water by answering the following question:
What effect does the addition of NaCl have on the boiling and freezing points of water? Hypothesis: Read introduction to Part 2.
Adding NaCl should lower the freezing point and raise the boiling point of water.
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Week 14 Materials: Bunsen burner, striker, ring stand, iron ring, wire gauze, 250 mL beaker (2), styrofoam cup (2), measuring spoon (tablespoon), thermometer (or Xplorer GLX datalogger and temp probe), glass stir rod, table salt (NaCl), distilled water, ice, safety glasses. Procedure: Refer to video lab. Record data below. Temp. Without Salt (°C)
Temp. With Salt (°C)
Boiling Point Elevation Freezing Point Depression
Results: Compare the temperatures with and without salt added.
Discussion:
1. Was your hypothesis correct? Why or why not? Yes, the boiling point was elevated and the freezing point depressed by the NaCl addition
2. List at least three sources of error. Instrument error, not enough data collected, recording error.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment. What are some other colligative properties of water?
What solute raises the boiling point of water the most?
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Week 15
LESSON 16: ACIDS, BASES, SALTS
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Acid, ionization, hydronium ion, hydroxide ion, base, indicators, pH scale, strong acid, weak acid, salt, neutralization 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 16 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-5) (1 pt. each) Circle the correct answer. 1)
Do bases accept or donate protons?
2)
Is the acid ion a hydroxide ion or hydronium ion?
3)
Does an acidic solution have a pH greater than 7 or lower than 7?
4)
Do strong acids or weak acids dissociate completely?
5)
Is the OH- ion called the hydroxide ion or hydronium ion?
Connection to Lesson 14: In the following neutralization reactions, fill in the blank with the appropriate compound. Also, make sure the equation is balanced. (3 pts. each)
NaCl ___________ + H2O
6)
HCl +NaOH →
7)
H2SO4 + Cu(OH)2 →
CuSO4 _______________
+ H2O
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Laboratory Activity
Week 15
14
Acid-Base Titrations As vinegar to the teeth and smoke to the eyes, so is the lazy man to those who send him.
Introduction
Proverbs 10:26
A titration is a technique that allows chemists to determine the concentration of an unknown solution by comparing its volume with the volume of a solution of known concentration. In a titration, the goal is to accurately measure volumes and neutralize one substance with another. By “neutralize”, we mean “equal amounts”, or “equivalents”, and in an acid-base titration, the equivalents are hydronium (H3O+)and hydroxide (OH-) ions. In our experiment, we will use a known concentration of the base Sodium Hydroxide (NaOH) to determine an unknown vinegar (acetic acid) concentration. To determine the vinegar's concentration we will use the equation
NbVb = NaVa Where N is the number of equivalents per liter of acid or base, and V is the volume in liters. By accurately measuring Nb, Vb and Va, we can determine Na. We will use the scientific method to answer the following question:
What is the acidity of household vinegar? Hypothesis: Read the label of the vinegar and record the % Acidity. Your hypothesis is correct if your % difference is ≤ 5%.
Methods
250 mL Erlenmeyer flask, 50 mL buret(2), 100 mL graduated cylinder, buret clamp, ring stand, eyedropper, wash bottle, funnel, safety glasses, 0.1 M NaOH, household vinegar labeled “5% Acidity”, Phenolphthalein, distilled water.
Procedure: Record data on following page.
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Week 15 Volumes
-
Trial 1 Acid volume (mL) Base volume (mL)
-
Trial 2 Acid volume (mL) Base volume (mL)
Results:
Calculuate vinegar's actual normality: Vinegar is Acetic Acid (HC2H3O2). Find its molecular weight, and use this to convert % Acidity (5 g Acid/100 g Vinegar) to Normality.
Calculate the vinegar's average experimental normality.
Discussion
_________________N
_____________________N
1. Was your hypothesis correct? Calculate % difference. ( larger-smaller/larger)
2. List at least three sources of error.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment.
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Week 16
Week 16 STUDY FOR
QUARTERLY EXAM 2 COVERS LESSONS 9-16
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Week 17
LESSON 17: ENERGY AND MOMENTUM
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Energy, potential energy, kinetic energy, joule, law of conservation of energy, radiant energy, mechanical energy, sound energy, thermal energy, chemical energy, photosynthesis, electrical energy, magnetic energy, nuclear energy, momentum, conservation of momentum, solar sailing 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 17 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-10) (1 pt. each) Circle the correct answer. 1)
Photosynthesis takes light (radiant) energy from the sun and converts it into __________________ energy. a)radiant b)mechanical c)sound d)electrical e)chemical f) magnetic
2)
A solar cell converts __________ energy to electrical energy. d)electrical e)chemical f) magnetic
3)
The motor in an electric fan converts electrical energy to _______________ energy b)mechanical c)sound d)electrical e)chemical f) magnetic
4)
A battery contains stored chemical energy, which can be transformed into _________________ energy, which in turn may be transformed into mechanical energy. a)radiant b)mechanical c)sound d)electrical e)chemical f) magnetic
5)
____________________ energy causes a compass to point towards the north pole. b)mechanical c)sound d)electrical e)chemical f) magnetic
6)
Mechanical energy is converted to ______________ energy when a drumstick hits a drum. b)mechanical c)sound d)electrical e)chemical f) magnetic
7)
In solar sailing, radiant energy is converted to ___________________ energy. c)sound d)electrical e)chemical f) magnetic
8)
The “boom” from an explosion is proof that some of the _________________ energy stored in the explosive is converted to sound energy. a)radiant b)mechanical c)sound d)electrical e)chemical f) magnetic
9)
When a quarterback throws the football, he is converting mechanical energy to _______________ energy. a)radiant b)mechanical c)sound d)electrical e)chemical f) magnetic
10)
When you lift a weight, your muscles convert _______________ energy stored in your cells into mechanical energy. a)radiant b)mechanical c)sound d)electrical e)chemical f) magnetic 66
a)radiant
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b)mechanical
a)radiant
c)sound
a)radiant
a)radiant a)radiant
b)mechanical
11)
Week 17 A 6 kg rock is sitting at the edge of a 100 m tall cliff. What is the potential energy of the rock with respect to the ground? (3 pts.) P.E. = mgh 6(9.8)(100) = 5880 J
12)
A skier coming off the ski lift at the top of the mountain has 221,000 J of potential energy. After skiing for two minutes, the skier has 135,000 J of potential energy left. How much of the skier’s initial potential energy was converted to other forms of energy? (3 pts.) 221,000 -135,000 86,000 J
13)
Name three of the possible forms of energy that the skier’s potential energy was converted to. (3 pts.)
14)
What is the kinetic energy of a 100 kg rocket traveling at 215 m/s? (3 pts.)
Kinetic, sound, heat
KE = 1/2mv2 .5(100)(215)2 = 2,311,250 J
15)
What is the rocket’s momentum? (3 pts.) mv 100(215) = 21,500 kg(m/s)
16)
Extra credit (3 pts.) A baseball sitting on the roof of the stadium has 60 J of potential energy. A pigeon lands on the baseball and knocks it off. How fast will the baseball be traveling the instant before it strikes the ground? Assume the baseball weighs 150 grams, and that all of the potential energy is converted into kinetic energy. 60J = 1/2(0.15)v2 120 = .15v2 v = 28.28 m/s
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Week 17
Laboratory Activity
15
Newton's 1st Law, Gravity, and Energy "And from true lordship it follows that the true God is living, intelligent, and powerful; from the other perfections, that he is supreme, or supremely perfect. He is eternal and infinite, omnipotent and omniscient, that is, he endures from eternity to eternity, and he is present from infinity to infinity; he rules all things, and he knows all things, and he knows all things that happen or can happen." Isaac Newton in The Principia, 2nd ed., 1713
Introduction
Isaac Newton was a Christian man and one of the greatest scientists in the history of the world, and his discoveries rank as some of the greatest scientific achievements ever. In the next three laboratory activities, you will study the three laws of motion he developed over 300 years ago. These laws are foundational to any study of motion. In Laboratory Activity 15, you will study Newton's 1st law of motion, and consider it in applications involving an object's center of gravity and in conversions of a snow skier's potential energy to kinetic energy.
Part 1: Newton's 1st Law Methods
Materials: Textbook or Internet Procedure: Record data below
-Define Newton's 1st Law: An object remains at rest or continues at the same velocity unless acted upon by an unbalanced outside force. -Define inertia: Resistance to a change in motion. - Describe 5 unbalanced forces that would cause an automobile to stop. Gravity, brakes, friction, air resistance, collision -What is the difference between speed and velocity? speed is "how fast", velocity is "how fast and in what direction" -What is the main way that we know an unbalanced force is being applied to an object? It experiences a change in velocity. 68
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Week 17
Part 2: Center of Gravity In explaining the forces of matter to his students, Michael Faraday (1791-1867) thought it was important to teach them how to find an object's center of gravity. Since one of the greatest experimental scientists of all time thought this was important, then we should too!
Methods
Materials: Coat hanger, paper, tape, permanent marker, straight edge, string, weight, foam block, forks (2) Procedure: Record data below
-Define Center of Gravity: The point where the whole gravitating force of a body is centered.
Find the Center of Gravity of a coat hanger.
-Was the center of gravity located on the coat hanger? No.
-Was the spot you marked the center of gravity? How do you know? Yes, because I was able to balance the hanger with one finger placed on that point.
Find the Center of Gravity of a foam block.
- At what point did the "plumb line" cause the block to fall over? What force was responsible for causing the "imbalance"? When it went outside the line on which the center of gravity lies. Gravity caused the imbalance.
Change the Center of Gravity of a foam block.
Why was it easier to hold the foam block when the forks pointed downwards? This position lowered the center of gravity of the "system".
If you had to design a car to maximize its stability, would you make it tall or short? Would you have most of the mass at the bottom of the car or on the top of the car? I would make a short car that had most of the weight on the bottom.
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Week 17
Part 3: Potential Energy and Kinetic Energy The following is some actual data collected on a ski trip to Wolf Creek, Colorado in 2001. Armed with a radar gun and altimeter, I clocked some of my students as they passed me after descending in a straight line without stopping. The goal was to convert all of their potential energy into kinetic energy. Here's the data: Initial Altitude = 10, 704 feet Final Altitude = 10, 608 feet Initial speed = 0.0 miles per hour Final Speed (two students tested) = 37.2 mph, 38.1 mph
Methods
Materials: Calculator Procedure: Record data below
What are the formulas for potential and kinetic energy? What are their units?
What was the change in altitude? Convert to meters.
What was the average final speed? Convert to meters per second.
______________m
_____________m/s
In theory, if all of the potential energy were converted to kinetic energy, what would the final speed have been? Set PE=KE and solve for v.
____________m/s
Calculate a % difference between theoretical and actual speeds ((|exp. - theor.|/theor.) x 100% List at least three forces acting on the skiers that could change their speed.
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____________%
Week 18
LESSON 18: VELOCITY AND ACCELERATION
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Mechanics, kinematics, dynamics, frame of reference, displacement, speed, average speed, velocity, magnitude, vector, scalar, acceleration 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 18 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-5) (3 pts. each) 1)
The air was moving 201 meters to the northeast every 12 seconds. At what speed was the wind traveling at?
2)
Driving at 65 mph, the trip from home to the cabin would take two and a half hours. How far was the cabin from home? d = vt = 65(2.5) = 162.5 mi
3)
If geese can fly at an average speed of 48 kph, how many hours would it take them to fly 1800 kilometers?
4)
The motorcycle went from 0 to 45 m/s in 4 seconds. How fast was the motorcycle accelerating?
5)
The fighter jet was accelerating at 60 m/s2. How many G’s was the jet pulling?
6)
The object slowed from 60 m/s to 20 m/s in 4 seconds. What was its acceleration during this time?
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Week 18
Laboratory Activity
16
Newton's 2nd Law and Acceleration "Surely this world-so beautifully diversified in its forms and motions-could not have arisen except from the perfectly free will of God, who provides and governs all things." Roger Cotes, editor of The Principia, 2nd ed., 1713
Introduction
The leading scientists of Isaac Newton's day understood that the God of the Holy Bible was the creator of the universe. And because order and purpose are attributes of His creation, scientists believed they could find some things out about how He governed the physical world. In Laboratory Activity 16, we will study Newton's 2nd law by measuring acceleration of a cart down an inclined plane. Newton's 2nd law relates force, mass, and acceleration in the following equation:
F=ma We learned in Laboratory Activity 15 that an object accelerates (changes velocity) when acted upon by an outside force. If you have ever been on a hill with a bicycle or other rolling object, you know there is a natural tendency for it to roll downhill. The reason for this is the Earth's gravitational force of attraction. Falling objects accelerate towards the earth's surface at the constant rate of 9.81 m/s2, which means that for every second of descent, their velocity increases by another 9.81 m/s. Air resistance and slight changes in the earth's gravitational attraction cause the value to fluctuate. An object rolling down a hill is similar to a free-falling object, but it is only affected by a fraction of the Earth's gravitational attraction. In Laboratory Activity 16, we will attempt to answer the following question:
Does inclination angle affect a cart's acceleration rate? Hypothesis: Read introduction and formulate a hypothesis. As the angle increases, acceleration down the incline should increase.
Methods
Materials: Xplorer GLX Datalogger, 2-axis acceleration sensor, 1-meter board for inclined plane, protractor, 100 g dynamics cart, tape. Procedure: Record data on the following page:
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Week 18 -Draw a free body diagram to determine how to predict the acceleration of a cart down an inclined plane:
Incline angle, Degrees 10 20 30
Theoretical Acceleration (m/s2)
1.70 3.36 4.90
Experimental Acceleration (m/s2)
% Error
Speed of Cart at bottom of incline (m/s)
Results: Calculate % Error for each inclination angle (|Theoretical-Experimental|/Theor.)100%.
Discussion
1. Was your hypothesis correct? Why? Yes, the acceleration increased with the inclination angle.
2. List at least three sources of error. Air resistance, friction, alignment of acceleration sensor.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment. Does mass of the cart affect its acceleration rate? How variable is the Earth's gravitational force?
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Week 19
LESSON 19: NEWTON’S LAWS
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Inertia, Newton (N), Newton’s 1st law, Newton’s 2nd law, gravity, Newton’s 3rd law, terminal velocity, weight, Universal Law of Gravitation, geostationary orbit, satellite 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 19 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-5) (1 pt. each) Circle the best answer. 1)
“For every action there is an equal and opposite reaction” is a statement made to explain a)Newton’s 1st law b)Newton’s 2nd law c)Newton’s 3rd law
2)
The formula, F=ma relates to
3)
Inertia is a word used to describe
4)
Force is measured in units of
5)
Objects used in racing (boats, cars, bobsleds, etc) are designed to b)minimize the Force to mass ratio c)change acceleration
6)
The watermelon was dropped from the top of the stadium, and impact with the ground occurred 4.5 seconds later. From what height was the watermelon dropped? (3 pts) d= 1/2at2 .5(9.8)(4.5)2= 99.23 m The first object had a mass of 600 kg, and the second object had a mass of 9000 kg. If the objects were 1 meter apart, use Newton’s Law of Universal Gravitation to determine the force of attraction between the two objects. (3 pts)
7)
F=
a)Newton’s 1st law
b)Newton’s 2nd law
a)Newton’s 1st law
a) Newtons
b) kg • m/s2
b)Newton’s 2nd law
c)Newton’s 3rd law c)Newton’s 3rd law
c) both a)maximize the Force to mass ratio
Gm1m2 6.67x10-11(600)(9000) = = 3.60x10-4N d2 12
8)
What would be a better design for a race car, an engine that could produce 1000 N of force mounted on a 200 kg car, or an engine that could produce 880 N of force mounted on a 150 kg car? Why? (4 pts)
9)
After the 0.15 kg baseball was hit, it accelerated at 200 m/s2. Determine the force with which the ball was hit. (3 pts.) F = ma 0.15(200) = 30 N 74 ©2010 Digital Interactive Video Education
Laboratory Activity
17
Week 19
Newton's 3rd Law and Applications "It is agreed that the supreme God necessarily exists, and by the same necessity he is always and everywhere." Isaac Newton in The Principia, 2nd ed., 1713
Introduction
In Lesson 1 you learned about deductive reasoning, which is what we do when we want to apply rules. Men like Aristotle and Euclid have taught countless individuals how to think deductively. When their teachings are connected with Scripture, we see that God is the ultimate "rule maker" and we apply His rules so that we know how He wants us to live. In Newton's day, the existence of God was a foundational truth in the lives of most scientists. In our day though, many scientists do not believe in God, but rather believe that man is the ultimate authority. Fortunately, more and more scientists are again trusting God and acknowledging the truth of His word. It was no accident that Isaac Newton and his Christian contemporaries made some of the greatest scientific discoveries in history. It is time for us to make some great discoveries again, but the only way this will happen is if we trust God and acknowledge Him as Creator of the universe and Savior of our souls. Belief in God is the only way we will make sense of the physical world.
In Laboratory Activity 17, we will study Newton's 3rd Law, which states that for every action, there is an equal and opposite reaction. If you push against a wall, it pushes back; a ship stays afloat because it is buoyed up by a force equal and opposite to its weight; the thrust of a rocket engine causes a mass to accelerate. These are a few of many examples of Newton's 3rd law. In Laboratory Activity 17, we will investigate Newton's 3rd Law, and we will apply all of Newton's Laws as we observe the impulse of a rocket engine. In physics, impulse is the amount of force imparted on an object over a time interval:
I = F∆t We will use impulse to answer the following question:
Is there a difference in the actual and observed impulse of an Estes model rocket engine? Hypothesis: No if % difference ≤ 5%
Methods
Materials: Xplorer GLX Datalogger, force sensor, rocket engine test bracket, ring stand, Estes A8-3 Rocket engines (3), 6V battery, insulated wire and alligator clips (4) or Estes Launch Controller, safety glasses. Procedure: Record data on the following page: 75
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Week 19 -Draw free body diagrams to describe the forces acting in the two situations shown:
Rocket engine thrust test, a=0 Incline angle, Degrees 10
Actual Impulse (N•s)
2.5
Observed Impulse 1 (N•s)
Rocket launch, a>0
Observed Impulse 2 (N•s)
Observed Impulse Ave. (N•s)
% Difference
Results: Calculate % Difference (|Actual-Observed|/Actual)100%. -The final speed of a rocket is directly related to the impulse created by the engine:
F∆t=m∆v
Using the Observed Impulse Average, calculuate the final speed in mph of a model rocket with a mass of 40 g.
Considering Newton's 2nd Law (F=ma), how would you design a rocket to maximize its acceleration?
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Week 19
Discussion
1. Was your hypothesis correct? Why? Yes, the % difference was only 2%
2. List at least three sources of error. Instrument error, alignment of test bracket, incomplete combustion of rocket fuel.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment. Is there a difference in predicted and experimental max. speed of a model rocket? Do environmental conditions effect performance of Estes rocket engines?
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Week 20
LESSON 20: WORK AND SIMPLE MACHINES
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Work, Joule, simple machine, lever, fulcrum, law of moments, torque, first-class lever, effort, effort arm, resistance, resistance arm, mechanical advantage, second class lever, third-class lever, wheel and axle, pulley, block and tackle, distance principle, inclined plane, wedge, screw, pitch, efficiency, power, watt 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 20 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. 1-15: True or False (1 pt each). 1) A screw is an inclined plane wrapped around a cylinder.
True
2) Work equals force times time.
False
3) Power equals work divided by time.
True
4) A wrench is an example of a third class lever.
False
5) A wheelbarrow is an example of a first class lever.
False
6) Your arm is an example of a third class lever.
True
7) Connection to lesson 17: The units for both kinetic energy and work are Joules.
True
8) Mechanical advantage equals resistance divided by effort.
True
9) Hinges are an example of a second class lever.
True
10) A fishing reel is an example of a block and tackle.
False
11) The mechanical advantage of an inclined plane equals the ratio of the length of the incline to the height perpendicular to the base.
True
12) Resistance is the force that you apply when using a simple machine.
False
13) Simple machines reduce the amount of work necessary to move an object
False
14) When using a simple machine, you “pay” for any reduction in effort by increasing the distance you must move the object.
True
15) Power is measured in Joules per second, or watts.
True
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Determine the mechanical advantage of the following objects (3 pts. each). 9m 16)
Week 20
3m
Inclined plane: 10 N effort needed to lift ball
17)
1st class lever:
25 N resistance
18)
Pulley 3
19) 60 N-m of torque was required to tighten the bolt. If the wrench that was used was 0.5 m long, how much effort was applied to tighten the bolt? 60 Nm = E(0.5m) 120 N
20) The hydraulic lift moved the 600 N package a distance of 50 meters in 12 seconds. How much power was required to move the package?
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Week 20
Laboratory Activity
18
Pulleys and 1st Class Levers Introduction In Laboratory Activity 18, you will compare theoretical and experimental results for pulleys and 1st class levers. Both devices are designed to make it easier to lift a large load, and apply the principle of mechanical work where work input equals work output. The load is often referred to as the resistance, R, and the amount of force required to lift it is the effort, E. The ratio of resistance to effort, R/E, is the system's mechanical advantage. In Laboratory Activity 18, we will not follow the scientific method directly, but will instead formulate a series of "hypotheses" by calculating theoretical results, and compare these to experimental values.
Methods
Materials: Action board and pin (or devise something to hang your pulley from), 10 to 1000 g hooked weight set, 0-250 g spring scale, single sheave pulley (2), pulley cord, demonstration balance, lever knife edge clamp (3), wooden meter stick that fits the knife-edge clamps.
Procedure: Refer to video lab and record data below:
Part 1: Pulleys Design the following three pulleys, and sketch each pulley/mass system in the space provided. Pulley 1 MA = 1 Resistance=200 g
Pulley 2 MA = 2 Resistance=200 g
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Pulley 3 MA = 3 Resistance=300 g
Week 20 Predict the effort required to lift the specified mass, measure the experimental effort, and calculate a % difference ((exp.-theor)/theor)*100. Pulley #
Theoretical Effort (g)
Experimental Effort (g)
% Difference
1 2 3 List several reasons why the experimental and theoretical results differed.
If the resistance in each of the pulley systems was lifted the same height, which one would use the most pulley string?
Part 2: 1st Class Levers What is an example of a device that acts like a 1st class lever? Design the following 1st class levers, predict the distance of the "effort" mass from the fulcrum, measure the experimental distance, and calculate a % difference. Use the space below to make calculations.
System #
Resistance Mass (g)
1
65.8 115.8
2
Resistance Distance from Fulcrum (cm)
40.0 20.0
Effort Mass (g)
65.8 65.8 81
Theoretical Effort Distance from Fulcrum (cm)
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Experimental Effort Distance from Fulcrum (cm)
% Difference
List several reasons why the experimental and theoretical results differed.
Week 20
Inaccurate masses, non-uniform mass of meterstick, differences in knife-edge clamp masses. If the lever arm were long enough and the fulcrum strong enough, could a human lift the Earth? Why or why not? Yes, because all you need is an effort arm long enough to reduce your effort down to a reasonable level.
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Week 21
No regular Assignment this week! Your assignment is to build a bridge. Watch Laboratory Activity 19 now for instructions.
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Week 21
Laboratory Activity
19
Bridge Building, 2nd and 3rd Class Levers Introduction Laboratory Activity 19 has two parts. In Part 1, which is also your Assignment for the week, you will build a bridge out of wooden splints. You will want to research bridge designs prior to construction, and there are many resources available for this. A good Internet site discussing bridge design is http://pghbridges.com. By following the rules listed below, you can compete with other students or family members in a bridge-building contest. And if you enjoy the competition, you may want to participate in the United States Military Academy's computer-based bridge building contest, which you can learn about at http://bridgecontest.usma.edu. In Part 2, you will continue the study of levers, comparing more theoretical and experimental results of 2nd and 3rd class levers.
Part 1: Bridge Building Methods
Materials: Wooden splints or popsicle sticks, Elmer's wood glue, scissors or x-acto knife, Rapala digital fishing scale that weighs to 50 lb,1/8" diameter rope, unbreakable object about 1" long to distribute weight on bridge.
Procedure: Refer to video lab:
If you are setting up a bridge-building contest, use the following rules:
1. 15 wooden splints. Do not use popsicle sticks, unless that is what everyone uses, but you may have difficulty breaking the bridges. These are the only splints you get and you cannot "replace" broken ones.
2. Minimum length = 2 wooden splints
3. Minimum width=2 wooden splints
4. Must be able to "drive" across bridge (no large gaps on surface)
5. Glue used cannot weigh more than the wooden splints.
6. The bridge must span a gap equal to the length of 1 wooden splint (about 5.5 inches)
7. There must be a way to suspend the rope and fishing scale from the center of the bridge. 84
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Week 21 If you have multiple students competing, set up a table similar to the one shown and record results.
Builder's Name or Bridge Type
Maximum Weight Supported (pounds)
Part 2: 2nd and 3rd Class Levers Methods
Materials: 10 to 1000 g hooked weight set, 0-1000 g spring scale, demonstration balance, lever knife edge clamp (4), wooden meter stick that fits the knife-edge clamps.
Procedure: Refer to video lab and record data below:
2nd Class Levers
What is an example of a device that acts like a 2nd class lever?
Design the following 2nd class levers, calculate the theoretical "effort" mass, measure the experimental effort, and calculate a % difference. Use the space below to make calculations.
System #
Resistance Mass (g)
1
500 500
2
Resistance Effort Distance Distance from from Fulcrum Fulcrum (cm) (cm)
10.0 10.0
Theoretical Effort (g)
40.0 20.0
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Experimental Effort (g)
% Difference
Week 21
List several reasons why the experimental and theoretical results differed. Inaccurate masses, non-uniform mass of meterstick, differences in knife-edge clamp masses.
3rd Class Levers
What is an example of a device that acts like a 3rd class lever?
Design the following 3rd class levers, calculate the theoretical "effort" mass, measure the experimental effort, and calculate a % difference. Use the space below to make calculations.
System #
Resistance Mass (g)
1
200 200
2
Resistance Effort Distance Distance from from Fulcrum Fulcrum (cm) (cm)
40.0 40.0
Theoretical Effort (g)
Experimental Effort (g)
10.0 30.0
Do 3rd class levers typically have a mechanical advantage greater or less than 1?
Why do you think God designed our bodies with so many 3rd class levers?
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% Difference
LESSON 21: PRESSURE AND FLUID DYNAMICS
Week 22
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Fluids, fluid mechanics, pressure, Pascal (Pa), Pascal’s principle, hydraulic machines, Archimede’s principle, Bernoulli’s principle 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 21 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-6) (3 pts. each) 1)
The diagram below is a cross section of an airplane wing. Identify the regions of higher and lower pressure when air is flowing over the wing.
2)
List three phenomena which could be understood by applying Archimedes’ principle.
-ducks floating -lead sinking -"weighing" less in water 3)
When the tennis ball hit the racket, a 50 N force was applied to a 0.0004 m2 area of the ball. What pressure was applied to the ball? 3
4)
The fluid inside the hydraulic jack had a pressure of 30,000 Pa. If the surface of the piston that is used to lift an object is 0.1 m2 in area, how much weight can the jack lift? 2
5)
Explain why the pressure is greater the deeper you dive underwater.
The deeper you go, the more fluid there is above you, so the more it weighs. Since P=F/A, the pressure increases. 6)
Use one sentence to explain why the force from atmospheric pressure doesn’t constantly try to push you down.
Pressure is equally distributed around you.
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Week 22
Laboratory Activity
20
Air Pressure, Buoyancy, and Fluid Force Introduction Laboratory Activity 20 is designed to help you better understand fluids like air and water. Anything that flows is a fluid, whether it is liquid or gas. Gases like air are sometimes difficult to understand, especially since we cannot see them. However, fluids are capable of generating tremendous forces, and these forces can be used by man for everything from flying to electrical power generation.
Part 1: Air and Water Pressure Methods
Materials: 250 mL Erlenmeyer flask, lighter or matches, balloon, stove or hot plate, plastic water bottle (approx. 500 mL), 1000 mL beaker or cooking pot, 2 L plastic soda bottle, rubber tubing, 250 mL beaker (2) Procedure: Refer to video lab:
Putting a water balloon in a flask:
Describe how the air pressure changed inside the flask after the water balloon covered the opening. The air pressure decreased because the air cooled down, and because some of the air (oxygen) was consumed by the flame, which meant fewer particles per square inch were hitting the balloon, compared to the outside.
Was the water balloon "sucked" into the flask, or "pushed" into the flask? How do you know? The balloon was pushed into the flask, because the pressure was higher outside. Air molecules did not pull or suck the balloon into the flask.
Was it easy or difficult to remove the balloon from the flask? Were the forces involved in putting the balloon in the flask large or small? Difficult; the forces involved in putting the balloon in the flask were large.
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Week 22
Crushing a plastic water bottle:
How did the air pressure inside the heated bottle compare to the atmospheric pressure immediately before closing it? They were the same.
How did the spacing of air molecules in the heated bottle compare to the atmosphere in the room immediately before closing it? Since they were warmer inside the bottle, they were spaced farther apart.
What crushed the water bottle when it was placed in an ice bath? The pressure decreased inside the bottle, and the outside atmosphere crushed the bottle.
Water pressure versus depth:
Describe the flow of water from the three openings in the 2 L plastic soda bottle. Why did the water flow faster from some openings? Water was flowing fastest from the bottom hole because it had the highest pressure due to the water above it.
Many reservoirs are built to generate electricity, and the generators are located at the reservoir's dam. Are they located on top or on bottom of the dam? Why? The bottom, because the pressure is highest there, and will have the most potential energy.
Potential energy and water flow:
Is air pressure or gravity the main reason water flows through the tube from a higher to lower elevation? Gravity is the main reason.
Why does the flow stop when the tube is momentarily removed from the higher beaker? Water molecules stick to each other, and will follow one another like cars in a train. If these connections are disruputed, then the water stops flowing.
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Week 22
Part 2: Buoyancy Methods: Materials: Cartesian Diver kit
Procedure: Refer to video lab. Record data below.
In order for an object to sink in water, its density must be greater than water's. How does pushing on the rubber screen increase the Cartesian diver's density? It increases the atmospheric pressure above the water, which also increases the water pressure, which in turn increases the air pressure inside the diver. The air is compressed, and more space is filled with water, increasing the overall density of the diver, and he sinks.
Some fishes have swim bladders, which are cavities that they can fill with air. Would a rapid decrease of air pressure (during a storm for example) cause fish to become more or less buoyant? More buoyant, their swim bladders would expand, making them less dense.
Sharks use oil to regulate their buoyancy. Why does oil work? Because oil is less dense than water, the more of it a shark makes, the less dense it becomes.
Part 3: Fluid Force Methods: Materials: Xplorer GLX Datalogger with force sensor, ring stand, dynamics cart, card stock paper (1 sheet),
tape, paper clip, two or three-speed fan. Procedure: Refer to video lab. Record data below.
What was the mean force imparted to the paper "sail" for the low and high settings?
0.3 Low setting = _________________N 0.4 High setting = ________________N
According to the Danish Wind Industry Association, one 2 MW wind turbine on a good location can cover the electricity consumption for 2000 households per year. What do you think they mean by "good location"? A place with consistent and high winds. 90
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LESSON 22: GAS LAWS
Week 23
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Boyle’s law, Charles’ law, Combined Gas law, barometer 3) Watch lecture and take notes. 4) Complete review questions, and check answers.
LESSON 22 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-6) (3 pts. each) 1)
The diver took a breath, and filled his lungs with 4 liters of air. The pressure of the air at the surface was 1 atm. He dove down 20 m, where the pressure was 3 atm. What was the volume of air in his lungs at 20 m deep?
P1V1= P2V2 1(4)=3V2 V2= 1.33 ℓ 2)
In order to regulate their buoyancy, some fishes are equipped with a swim bladder. Red snapper are a type of fish that has a swim bladder. A snapper swimming at 20 m deep had a pressure of 2 atm pressing on it from the surrounding water. It’s swim bladder had a volume of 1 liter. The snapper swam to 45 m deep, and it’s swim bladder shrunk to a volume of 0.45 liters. What was the water pressure at 45 m?
2(1)= P2(0.45) P2=4.44 atm
3)
Scuba divers are trained to always be exhaling some amount of air, especially when they are ascending. Use Boyle’s law to explain why this is important.
as P↓, V↑ lungs could rupture
4)
The tire had an initial volume of 7 liters, at a temperature of 25° C. After driving for an hour, friction from the road had increased the temperature of air in the tire to 35° C. Assuming the pressure inside the tire did not change, what would the tire’s new volume be? 2
7(308) = 298 V2 V2 = 7.23 ℓ
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Week 23 5) The initial volume of air in the rubber balloon was 2 liters, and it was at a temperature of 293 K. The balloon was placed in the parked car, where the volume increased to 2.5 liters. What was the temperature inside the parked car in °C? 2T2 = 732.5 T2 = 366.25 K -273 93.250C 6)
The diver’s air tank had an initial temperature of 20° C, a pressure of 3000 psi, and a volume of 10 liters. If the air in the diver's lungs warmed to 35° C at a pressure of 15 psi, how much air could the tank supply to the diver? 11
2 2
1
2 2
9,240,000 = 4395V2 V2 = 2,102.39 ℓ
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Laboratory Activity
21
Week 23
Boyle's and Charles' Laws Introduction Robert Boyle (1627-1691) is considered one of the greatest scientists of all time, and the father of modern chemistry. He was also a humble Christian man. He was profoundly interested in missions, devoting much of his own time and money to Bible translation work and the propagation of the gospel. In high school science, his name is most often associated with the following formula known as Boyle’s Law. For an ideal gas: P1V1=P2V2 Another way to think about Boyle’s Law is that when temperature is constant, pressure and volume of an ideal gas are indirectly related. In the 1800's, the French scientist Jaques Charles employed some of the same techniques Boyle used to compare pressure and volume. Holding pressure constant, Charles observed that a direct relationship exists between temperature and volume of a gas: V1/T1 = V2/T2 In Laboratory Activity 21, we will use the scientific method to answer questions relating to Boyle's Law and Charles' Law.
Methods
Equipment: Boyle’s Law apparatus (50 mL syringe, pre-cut wooden blocks), 2-gallon or larger plastic container, Digimano digital pressure meter, rubber tubing, barometer, thermometer, teflon tape, oven, freezer, Microsoft Excel or similar software (or Texas Instruments Graphing Calculator).
Procedure: Refer to video lab. Record your data on the following page
Question 1 Is there an indirect relationship between pressure and volume of an ideal gas? Hypothesis: See Introduction.
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Week 23
Atmospheric pressure at time of experiment:
Volume (mL)
50 45 40 35 30
Meter Pressure Meter + Atmospheric (psi) Pressure (psi)
_________________psi
Pressure x Volume
Results:
Graph pressure (y-axis) versus volume (x-axis) in Microsoft Excel, and observe whether the trend is direct or indirect.
Discussion:
1. Was your hypothesis correct? Yes, as pressure increased, volume decreased
2. List at least three sources of error. Temperature not constant, instrument error, measurement error
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment. Does temperature increase when a gas is compressed? Are pressure and density of a gas related? 94
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Question 2 Is there a direct relationship between pressure and volume of an ideal gas?
Week 23
Hypothesis: See Introduction.
Record Data below:
Volume (mL)
Temperature (°C)
Results:
Graph temperature (y-axis) versus volume (x-axis) in Microsoft Excel, and observe whether the trend is direct or indirect. Use the "add trendline" function to calculate R2 and to generate a linear equation. R2 = _____________________ Equation:_______________________________________ Using the equation above, determine the temperature at which the volume = 0, a.k.a. "absolute zero"
Predicted value for absolute zero = ______________ °C
Discussion:
1. Was your hypothesis correct? Yes, as temperature increased, volume increased
2. List at least three sources of error. Pressure not constant, instrument error, measurement error
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment. Is Charles' Law linear near absolute zero? Are pressure and temperature directly related? 95
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Week 24
Week 24 STUDY FOR
QUARTERLY EXAM 3 COVERS LESSONS 17-22
and
LAB ACTIVITIES
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15-21
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LESSON 23: THERMODYNAMICS
Week 25
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Heat, caloric theory, kinetic theory, temperature, calorie (cal), kilocalorie (kcal), conduction, thermal equilibrium, conductors, insulators, R-value, convection, convection current, radiation, thermodynamics, entropy, specific heat, heat of fusion, heat of vaporization, thermal expansion 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 23 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-10) True or False (1 pt. each) 1)
Thermal energy is transferred from one end of a metal pipe to another by conduction.
2)
The sun heats a surface by convection.
3)
Materials with high R-values are good insulators.
4)
The energy content of foods is usually measured in Cal.
5)
An example of conduction is the mixing of cold air with warm air.
True
False True True
False 6)
Temperature is a measure of the average kinetic energy of a substance.
7)
The amount of heat required to melt a solid at its melting point is called the heat of vaporization.
8)
The kinetic theory states that only particles in gases are constantly moving.
9)
Entropy is a way to describe the only usable form of energy.
10)
Two objects that are touching are said to be in thermal equilibrium when their temperatures are the same.
True
False False False True
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Week 25 11) Explain the difference between conduction and convection. Give one example of each as well. (3 pts.)
In conduction, energy is transferred from one particle to the next by collisions. An example would be heat transfer through a metal. In convection, fluid particles of difference temperatures mix together. Convection does not occur in solids. An example of convection would be mixing cold milk in hot coffee.
12)
If 500 cal of heat were added to 50 g of water and to 50 g of aluminum, which substance’s temperature would increase more? Why? (3 pts)
Aluminum, because it has a lower specific heat and will therefore have a greater temperature change for the same amount of heat input.
13)
The heat of fusion of gold is 15.9 cal/g. How much heat is required to melt one ounce (28.35 g) of gold that is at its melting point? (3 pts)
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22 Specific Heat of a Metal
Week 25
Laboratory Activity
Introduction Specific heat is defined as the amount of heat required to raise the temperature of 1 g of a substance by 1 °C. The term originated primarily through the work of Scottish physicist Joseph Black who conducted various heat measurements and used the phrase “capacity for heat” (en.wikipedia.org). Water has one of the highest specific heats at 1.0 cal/g•°C. We can use the specific heat of water to determine the specific heat of an unknown sample. An unknown is heated and placed in cool water of known temperature. The unknown/water mixture is allowed to equilibrate, and the final temperature of the mixture is recorded. The amount of heat transferred to the water is calculated using the following equation: Q=mCsp∆T where m is the mass in grams, Csp is specific heat, and ∆T is the temperature change. To determine the unknown's specific heat, it is assumed that the heat gained by the water is equal to the heat lost by the sample, and the following equation is solved for the Cu, the unknown's specific heat. mwCw∆Tw = muCu∆Tu Cu = mwCw∆Tw/mu∆Tu
In Laboratory Activity 22, we will use the scientific method to answer the following question:
Can we determine the specific heat of several metals experimentally? Hypothesis: Yes if mean % error ≤ 5% Methods
Equipment: Digital Balance, 250 mL Beaker, 100 mL graduated cylinder, metals of similar mass (copper, cadmium, lead), thermometer (can use Xplorer GLX temperature probe), styrofoam cup (2), pliers or crucible tongs, water.
Procedure: Refer to video lab. Record your data on the following page.
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Week 25 Record the mass of water in the cup: Metal
Copper Cadmium Lead
Mass (g)
Initial Metal Temperature (°C)
Initial Water Temperature (°C)
100.0 100.0 100.0 Metal
Actual Specific Heat (cal/g•°C)
Copper
0.092 0.055 0.031
Cadmium Lead
Results:
______________g
Final Metal and Water Temperature (°C)
Observed Specific Heat (cal/g•°C)
∆T Water
∆T Metal
(°C)
(°C)
% Error
Calculate the specifc heat of each metal and it's percent error.
Discussion:
1. Was your hypothesis correct (mean % error ≤ 5%)?
2. List at least three sources of error.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment.
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LESSON 24: STATIC ELECTRICITY
Week 26
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Static electricity, law of charges, capacitors, induction, electroscope 3) Watch lecture and take notes. 4) Complete review questions, and check answers.
LESSON 24 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-5) (3 pts. each) 1)
Explain why your clothes and hair seem more “staticky” on cool dry days than on humid days.
On humid days, water molecules in the air attract the electrons on the surface of your body and on clothing. On dry days, water is not as plentiful, which allows charges to build up. Since like charges repel, your hair may "stand on end", and you may receive a spark when you come in contact with a conductive object.
2) Sketch what would happen to the leaves of the electroscope if a negatively charged balloon was brought close (but not touching) to it. Answer:
3)
Sketch what would happen to the charges in the wall if a negatively charged balloon touched the wall. Answer:
4)
Define the law of charges.
The law of charges states that like charges repel and opposite charges attract.
5)
Discuss why electrons, and not protons, are responsible for making an object “charged”.
Electrons, particularly valence electrons, are free to move, while protons are bound tightly to the nucleus of an atom. Therefore, in order for an object to be negatively charges, it must have an excess of electrons. Objects become positively charged by losing their electrons. 101
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Laboratory Activity
23
Static and Current Electricity "Let us now examine a vessel containing the acid liquid and the slips of zinc and copper, and I have them touching each other outside by means of a wire coming from each of them." Michael Faraday in The Forces of Matter
Introduction
Michael Faraday (1791-1867) grew up in a poor family in London, and with almost no formal education, had to largely educate himself. He eventually became one of the greatest scientists of all times. Michael Faraday was a devout Christian and a member of the small Sandemanian denomination, an offshoot of the Church of Scotland. He later served two terms as an elder in the group's church. Although Faraday had many accomplishments, his greatest work was with electricity and magnetism (en.wikipedia.org). In Laboratory Activity 23, we will duplicate some of the same experiments Faraday used in the 1800's to teach his students about static and current electricity.
Part 1: Static Electricity Methods
Equipment: Plastic rod, metal rod or spatula, Scotch tape, fur, wool or silk (4-inch square), plastic comb, copy paper, rubber balloon, scissors.
Procedure: Refer to video lab. Record your data below:
Define Static Electricity: The imbalance of positive and negative charges.
Detecting Charges:
What happened when the "unrubbed" plastic rod was placed near the paper squares? Nothing.
What happened when the rubbed plastic rod was placed near the paper squares? Some of the squares were attracted to the rod.
Explain the difference in the rubbed and unrubbed plastic rod. The contact between two insulated materials created an imbalance of charges. Excess charge on the rubbed rod caused the paper to be attracted. 102
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Week 26
Why wouldn't the rubbed or unrubbed metal deflect the paper squares? Because metal is conductive and the electrons are not stationary, but move freely through the metal. What is the difference between a conductor and an insulator? electrons move freely through a conductor, but are collected on the surface of an insulator
What is the "charge" that builds up on the rubbed plastic rod? Electrons
Opposite Charges
Test 1) Quickly remove two pieces of Scotch tape from a table. Slowly bring them back together and describe the results.
They repel each other. They must have aquired an excess of the same charge. Test 2) Quickly pull two pieces of Scotch tape apart. Slowly bring them back together and describe the results. They are attracted. One piece "stole" charge from the other.
An Excess of Electrons Object
Tape A (attract or repel)
Tape B (attract or repel)
Comb Plastic Rod Balloon
Which had an excess of electrons, tape A or B?
Electric Fields and Forces:
Was the rubbed plastic comb able to deflect the water?
Are electrons capable of generating forces?
What is an electric field? The space around an electric charge that exerts a force on other charged objects.
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Week 26
Part 2: Current Electricity and the Voltaic Cell Methods
Equipment: Digital Multimeter or Xplorer GLX Datalogger, 150 mL glass beaker, vinegar, 3-inch strips of Copper and Zinc (2 each),
Procedure: Refer to video lab. Record your data below: Test
Voltage (Volts)
Cu + Cu Cu + Zn Zn + Zn
Which test resulted in the highest voltage reading? Why do you think this was?
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LESSON 25: CURRENT AND OHM’S LAW
Week 27
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Electric current, conductors, insulators, semiconductors, circuit, switch, short circuit, volts (V), coulomb (C), amperes (A), resistor, Ohm’s law, ohms (Ω), load, series circuit, parallel circuit, fuse, circuit breaker, watt, kilowatt (kW) 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 25 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-10) Fill in the blanks using the following words. Use each word only one time (1 pt. each).
Amps, current, fuse, insulator, ohms, parallel, semiconductor, series, voltage, watts 1)
semiconductor Carbon is an example of a _______________________ .
2)
current The flow of electrons is known as ____________________ .
3)
series In a ________________ circuit, the current is the same everywhere.
4)
parallel In a __________________ circuit, the voltage is the same everywhere.
5)
watts Electrical and mechanical power both have units of ____________________.
6)
insulator Rubber is a good ______________________________.
7)
voltage The force on an electron is known as ___________________________.
8)
ohms Resistance is measured in ___________________________.
9)
amps Current is measured in ___________________________.
10)
fuse A ____________________ is designed to create a short circuit when a circuit receives an excess of current.
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Week 27
11)
List three materials that are good conductors of electricity, and three materials that are poor conductors of electricity (2 pts)
Good: copper aluminum gold
Poor: rubber wood plastic
12)
The load had a resistance of 225 ohms. If the applied voltage was 12 volts, what was the value of the current passing through the load? (3 pts.)
13)
A 9 volt battery was required to operate the flashlight. If there was a 0.2 amp current passing through the flashlight, then what was the resistance of the flashlight? (3 pts.) V = IR
14)
Extra credit. Connection to Lessons 17 and 20. The electrical source supplied electrical energy to the hydraulic lift at the rate of 500 watts. At this rate, how long would it take to lift a 2000 N box 5 meters? Assume all electrical energy was transferred to mechanical energy. (3 pts.)
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Laboratory Activity
24
Week 27
Electric Circuits "Now observe this: here is a piece of wire which I am about to make into a bright force, that is to say, a communicator between the two ends of the battery. You see that before the circuit is completed, it has no power over the magnet. But observe it when I make contact..." Michael Faraday in The Forces of Matter
Introduction
In Laboratory Activity 24, we will continue our investigation of electricity. We will see how electricity and magnetism are related. Michael Faraday made some of the foundational discoveries in electricity and magnetism. It is no accident that this Christian man, who worshipped the true God who has a triune nature (Father, Son, Holy Spirit), could understand that natural phenomena can also possess multiple natures. Faraday was not the first man to study electricity, but his solid relationship with the Creator helped him understand electricity better than anyone previously had. In Laboratory Activity 24, you will study the dual nature of current electricity, and you will learn how to build two types of electrical circuits.
Part 1: Magnetism and Current Electricity Question: Is there a correlation between voltage and magnetic field strength? Hypothesis: Yes if R2 ≥ 0.95
Methods
Equipment: Magnetic compass, 16 gauge insulted copper wire (5 ft), D-cell batteries (4), battery holders (4), miniature 6V lamps and lamp bases (4), alligator clips (10), tape. Procedure: Refer to video lab. Record your data on the following page:
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Week 27 Record data in the following table:
Voltage (Volts)
Deflection (Degrees)
0.0 1.5 3.0 4.5 6.0
Results:
Use Microsoft Excel or a similar program to create a linear regression model of the deflection angle (y-axis) versus battery voltage (x-axis).
Equation:__________________________
R2:___________________________
Discussion:
1. Was your hypothesis correct? Why or why not? Yes, R2=0.95
2. List at least three sources of error. Actual battery voltage different from labeled voltage, measurement error, voltage drop in circuit from lamp.
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment. Is there a correlation between current and magnetic field strength? Is there a correlation between power and magnetic field strength? 108
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Week 27
Part 1: Series and Parallel Circuits Methods
Equipment: See Part 1 Procedure: Refer to video lab. Record your data below by checking the appropriate box:
For which circuit is the current the same everywhere? For which circuit is the voltage the same everywhere? Which circuit shuts down when one or more lights is removed? Which circuit remains closed when one or more lights is removed? How is your house "wired"?
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Series Circuit
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Parallel Circuit
Week 28
LESSON 26: MAGNETISM AND ELECTRICITY
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Magnetic poles, electric field, lines of force, magnetic field, ferromagnetic, paramagnetic, domains, ferrimagnetic, Curie temperature, geographic north, magnetic north, solenoid, relay, generator, alternating current (AC), hertz (Hz), direct current (DC), step-up transformer, step-down transformer, superconducting magnets, armature 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 26 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-10) Fill in the blanks using the following words. Use each word only one time (1 pt. each).
Alternating, changing, Curie, direct, electric, ferrimagnetic, ferromagnetic, magnetic, step-down, step-up 1)
ferromagnetic The materials that are attracted by magnetic fields are said to be _________________________.
2)
Curie The ______________ temperature is the temperature at which a substance no longer exhibits magnetism.
3)
electric ___________________________ field lines are always drawn pointing away from positive charges.
4)
magnetic _________________________ field lines are always drawn pointing towards south magnetic poles.
5)
ferrimagnetic Materials that are naturally magnetic are said to be ____________________________________.
6)
alternating Power plants produce _____________________________________ current.
7)
direct Battery-powered devices operate using ____________________________________ current.
8)
step up In a ________________________ transformer, the voltage produced in the second coil is greater than the voltage in the first coil.
9)
step down _______________________ transformers are used to reduce the voltage carried in power lines for use in your house.
10)
changing Electrical current can be generated by a _________________________ magnetic field.
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11)
Week 28 The step-down transformer was used to convert voltage from the power lines (11,000 V) to standard household voltage (110 V). If the power line side of the transformer had 1000 coils, how many would the household side need? (3 pts.) 1 1 2
2
1
2
1000 = 100N2 N2 = 10 12)
Explain why an AC motor would not need a split ring (A split ring is the gap in the commutator from the lecture on a DC motor). (3 pts.)
13)
Use the right hand rule to sketch the direction of the magnetic field around this wire. (2 pts)
In a DC motor, the purpose of a split ring is to alternate the current, which reverses the magnetic field in the armature and keeps the motor spinning. Since AC current is already alternating, there is no need for a split ring.
current direction
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Week 28
Laboratory Activity
25
Magnetic Fields and Electromagnets "Furthermore, if I take an iron bar, and put it inside the coil, so long as there is no electric current circulating round, it has no attraction [to the nails]. But now, if I make contact with the battery, they are attracted at once." Michael Faraday in The Forces of Matter
Introduction
In Laboratory Activity 25, we will continue our investigation of electric current by studying permanent magnets and electromagnets by duplicating some of the experiments Michael Faraday taught his own students when introducting them to electricity and magnetism.
Part 1: Magnetic fields Methods
Equipment: cardstock paper (1 sheet), iron filings, bar magnets (2)
Procedure: Refer to video lab. Record data below.
Sketch the magnetic field around each bar magnet arrangement shown:
N
N
N
S
S
S
N
S
N
S
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Week 28 Are actual magnetic fields 2-dimensional or 3-dimensional? Are actual magnetic fields continuous or composed of lines?
Part 2: Electromagnets and # Coils Question: Is there a linear correlation between the # coils and an electromagnet's strength? Hypothesis: Yes if R2 ≥ 0.95 Methods
Equipment: 3" Iron bolt, 16 gauge insulted copper wire (5 ft), D-cell batteries (1), battery holders (1), iron finishing nails (100). Procedure: Refer to video lab. Record your data below:
# Coils
10
Trial 1
Trial 2
# Nails
Trial 3
Mean
20 30 40 50 Results:
Use Microsoft Excel or a similar program to create a linear regression model of the # nails (y-axis) versus #coils (x-axis).
Equation:__________________________
R2:___________________________
Use the equation to predict how many nails you could pick up if there were 35 coils.
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________nails
Week 28
Discussion:
1. Was your hypothesis correct? Why or why not? Yes, R2 = 0.98, so there was a linear correlation between #Coils and magnetic field strength
2. List at least three sources of error. Changes in battery voltage, counting errors, differences in nail masses
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment. What is the effect of battery voltage on magnetic field strength? Is there a point when the relationship between #coils and electromagnet strength becomes nonlinear?
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LESSON 27: SOUND WAVES
Week 29
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Sound, wave, compression, rarefraction, tone, pitch, frequency, infrasonic wave, ultrasonic wave, loudness, decibel (db), threshold of hearing, amplitude, acoustics, resonance, beats, Doppler effect, sonar, echolocation, ultrasound 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 27 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-15) True or False (1 pt. each) 1)
The loudness of a sound is measured in Hz.
2)
The loudest tone produced by an instrument is called the fundamental tone.
3)
The speed of a sound wave is inversely proportional to the density of the material through which it is passing.
4)
Humans apply the method of echolocation used by some animals in designing sonar devices.
5)
The tone of a sound is determined by its frequency.
6)
The loudness of a sound is determined by its amplitude.
7)
The threshold for hearing is about 80 db.
8)
Sound travels faster in a vacuum than in air.
9)
As a train that is honking its horn approaches you, the pitch you will hear will be lower than the horn’s actual pitch.
10)
A building that has consistent sound quality throughout is said to have good acoustics.
11)
Natural frequency is the frequency at which an object will resonate.
12)
The speed of sound is faster in water than in air.
13)
We cannot hear infrasonic and ultrasonic waves.
14)
If two sound waves have slightly different frequencies, an interference pattern develops that produces alternating high and low intensities, or beats.
15)
Rarefied air is the air in between successive compression phases of a sound wave.
False True
False True True True
False False False True True True True True True
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Laboratory Activity
26
Week 29
Properties of Sound Introduction In Laboratory Activity 26, you will learn about the basic properties of waves and observe several demonstrations with sound waves.
Methods:
Materials: Xplorer GLX Datalogger with General Science sensor, bell jar, vacuum pump, silicon sealant, battery operated alarm, 18" sound resonating tube, meter stick, 288 Hz (D') aluminum alloy tuning fork, slinky.
Procedure: Refer to video lab. Record data below.
Transverse and Longitudinal Waves
Label the following components of a transverse wave: crest, trough, wavelength, amplitude.
Copied with permission from commons.wikimedia.org
Define Frequency: Number of wavelengths that pass a given point in 1 second; number of occurrences of an event in a given time period.
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Week 29
Does the energy move perpendicular to the motion in a transverse or longitudinal wave?
Does the energy move in the same direction as motion in a transverse or longitudinal wave?
Is a sound wave a transverse or longitudinal wave?
Standing waves
The point of a standing wave where no motion occurs is called a _______________.
Create the fundamental frequency, first overtone (1 node), and 2nd overtone (2 nodes) with the Slinky and sketch below:
|
|
Fundamental Frequency
|
|
First Overtone
What gives a musical instrument its characteristic sound? Mixture of fundamental frequency and overtones
The Speed of Sound (v=f λ)
Frequency of tuning fork = ___________Hz
Length of tube at point of resonation = _____________m
Speed of sound
_________________m/s
Theoretical Speed of Sound =
_________________m/s
Amplifying Sound
How did the Amplifier make the sound louder? It focused the sound waves in one direction.
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|
|
Second Overtone
Week 29
Is there sound in outer space?
Was the alarm louder or quieter after air was pumped from the bell jar? Quieter
Is there sound in space? Why or why not? No, because there is nothing to compress or rarefact
Measuring sound intensity
Record data in the table shown:
Distance From Source (feet)
0 1 2 3 4
Loudness (Decibels)
Does the data display a direct or indirect relationship between sound intensity and distance from the source? Indirect, as distance increases, loudness decreases
Do you think the relationship is linear or nonlinear?
Nonlinear, drops by 11 dB, then 4, 3, and 2 140 What sound intensity is considered as the threshold for pain? _________________dB (A)
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LESSON 28: ELECTROMAGNETIC WAVES AND LIGHT
Week 30
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: Mechanical waves, crests, troughs, amplitude, wavelength, frequency, hertz, velocity, transverse wave, longitudinal wave, constructive interference, radio wave, microwave, radar, infrared wave, prism, incandescent, ultraviolet light, x-ray, gamma ray, visible light, line spectrum, additive primary colors, subtractive primary colors, intensity, candela (cd), inverse square law 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 28 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-15) Circle the correct answer. (1 pt. each) 1)
Does a radio wave have more or less energy than a microwave?
2)
Does an x-ray have more or less energy than a gamma ray?
3)
Does the energy of an electromagnetic wave increase with increasing frequency or increasing wavelength?
4)
Is a sound wave a longitudinal wave or a transverse wave?
5)
Is a wind generated wave on the surface of the ocean a transverse wave or a longitudinal wave?
6)
Do radar detectors use radio waves or microwaves?
7)
Does an infrared wave have less energy or more energy than visible light?
8)
Are X-rays or gamma rays used to treat cancer?
9)
Does ultraviolet light have more or less energy than visible light?
10)
Is the intensity of light directly proportional to the square of the distance from the light source, or inversely proportional to the square of the distance from the light source?
11)
Is red or yellow an additive primary color?
12)
Is red or yellow a subtractive primary color?
13)
Does light travel faster in air or water?
14)
Is the SI unit for light intensity a candela or a lumen?
15)
Does an illuminated object reflect or emit light waves?
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Week 30 16)
If the speed of light is 3.00 x 108 m/s, determine the wavelength of an electromagnetic wave with a frequency of 1 million Hz. (3 pts.) v = fλ 3 x 108 = 1 x 106(λ) 300 m
17)
Extra credit (3 pts.) Is the electromagnetic wave described in problem 16 a microwave or a radio wave?
18)
Sketch a transverse wave, and identify its crest, trough, amplitude, and wavelength. (4 pts.) crest λ
Radio wave
A
trough
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Laboratory Activity
27
Week 30
Solar Power Introduction Solar power generally refers to the conversion of sunlight into electricity. There is currently great interest in utilizing renewable forms of energy, and as the pie chart below shows, solar power is currently a very minor contributor to the United States energy needs. Nevertheless, production of photovoltaic cells has been doubling every two years, so it is good to be familiar with this increasingly popular form of renewable energy.
The Role of Renewable Energy Consumption in the Nation’s Energy Supply, 2007 Courtesy of U.S. Energy Information Administration
You have learned about several forms of energy that man uses, including hydrocarbons, coal, nuclear, and wind power. In Laboratory Activity 27, you will learn about the effects of light levels on performance and efficiency of solar cells.
Methods:
Materials: Xplorer GLX Datalogger with General Science sensor (or digital multimeter), 1.5 V solar cell, alligator clips (2), black window screen (5 square feet). Procedure: Refer to video lab. Record data on following page.
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Week 30
Part 1: The effects of light levels on photovoltaic performance. Question: Is there a linear correlation between light levels and photovoltaic performance? Hypothesis: Yes if R2 ≥ 0.95 Methods
Equipment: see p. 121. Procedure: Refer to video lab. Record your data below: # screens
0
Voltage
% of Maximum
1 2 3 4 5
Results:
Use Microsoft Excel or a similar program to create a linear regression model of the % Max. (y-axis) versus #screens (x-axis).
Equation:__________________________
R2:___________________________
Describe a location that would be optimal for maximizing the production of solar power. Few clouds and at a latitude to maximize light levels.
Describe some of the disadvantages of relying only on solar power for electricity. Use limited to daylight hours only unless batteries used. Output fluctuates with cloud cover.
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Week 20
Discussion:
1. Was your hypothesis correct? Why or why not?
Yes, there was a linear correlation between light levels and photovoltaic performance (R2 = 0.99). 2. List at least three sources of error. instrument error, changes in light intensity during experiment, calculation errors
3. Considering the question answered in this experiment, list some similar questions that could be answered by conducting a science experiment. Is there a correlation between outside temperature and photovoltaic performance? What is the efficiency of sunlight to electrical energy conversion of a solar cell?
Part 2: The effects of light intensity on photovoltaic cell voltage. In Part 1, we did a qualitative comparison of light on the performance of a photvoltaic cell. In that experiment, we had the cell running at maximum performance. However, solar cells can only produce so much voltage, and when they reach their maximum, then they won't go any higher, regardless of the intensity. In Part 2, you will collect quantitative data on light levels vs. voltage, using light levels that do not maximize the solar cell's output. You will answer the following question:
Question: Is there a linear correlation between light intensity and photvoltaic cell voltage? Hypothesis: Yes if R2 ≥ 0.95 Methods
Equipment: see p. 121. Procedure: Refer to video lab. Record your data below: Light Intensity (Lux)
Voltage (Volts)
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Week 30
Results:
Use Microsoft Excel or a similar program to create a linear regression model of the Voltage (y-axis) versus light intensity(x-axis).
Equation:__________________________
R2:___________________________
Describe an alternative hypothesis for this experiment.
Does the trend suggest that the solar cell has a maximum voltage that can go no higher, regardless of the light level? Yes, the curve "flattens out" at higher intensities.
Describe the disadvantages of this type of solar cell. It cannot take advantage of the brightest days, which would be best for converting sunlight to electricity.
Discussion:
1. Was your hypothesis correct? Why or why not? No, a nonlinear pattern explained the relationship between voltage and light intensity.
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LESSON 29: REFLECTION AND REFRACTION
Week 31
Assignment: 1) Read textbook pages corresponding to this topic. 2) Define the following terms: beam, ray, normal, incident ray, reflected ray, angle of incidence, angle of reflection, law of reflection, laser, coherent light, plane mirror, virtual image, concave mirror, principle focus, real image, refraction, lens, focal length, dispersion 3) Watch lecture and take notes. 4) Complete review questions, and check answers. LESSON 29 REVIEW QUESTIONS Solutions are at the end of the video for this lesson. (1-10) (1 pt. each) Circle the correct answer. 1)
Is the lens in your eye shaped more like a concave or convex lens?
2)
Is the normal drawn perpendicular or parallel to the reflecting surface?
3)
Does a plane mirror or a concave mirror produce real images?
4)
Does a laser produce coherent or incoherent light?
5)
Does the angle of incidence equal the angle of reflection or angle of refraction?
6)
Does a plane mirror or a concave mirror always produce virtual images?
7)
Are virtual images formed in front of or behind the mirror?
8)
Is the focal length measured for plane mirrors or concave mirrors?
9)
Is the formation of a rainbow the result of dispersion or collecting of light?
10)
Are lenses mainly used to reflect or refract light?
11)
Use the properties of a concave mirror to describe how a flashlight works. Use words as well as a sketch. (4 pts.)
light at focal point
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Week 31
Laboratory Activity
28
Reflection and Refraction And God said: "This is the sign of the covenant which I make between Me and you, and every living creature that is with you, for perpetual generations: I set My rainbow in the cloud, and it shall be for the sign of the covenant between me and the earth." Genesis 9:12-13
Introduction God of course understands His creation better than any of us ever will, and we see how He used the properties of light to give Noah and subsequent generations a sign of the covenant He made to not destroy the earth with water again. In Laboratory Activity 7, you learned about the light given off by electrons as they fell to lower energy levels around an atom, and you learned that different colors of light correspond with different wavelengths. In Laboratory Activity 28, we will study light's properties of reflection and refraction.
Methods: Materials: Optics kit with double-convex lens (20 cm focal length), meter stick, candle, lighter, pins (5),
mirror (3"x5"), ruler, 12" cardboard square, protractor. Procedure: Refer to video lab. Record data below.
Part 1: Reflection
Remove page 127 from your binder and use it to perform the experiment. Fill in the table below. Angle
Measure (degrees)
i1
r1 i2 r2
-How do the image and object distance compare? Should they be the same?
-How do i1/r1 and i2/r2 compare? Should they be the same?
-How do i1/i2 and r1/r2 compare? Should they be the same?
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Week 31
Line up mirror here
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©2010 Digital Interactive Video Education
Week 31
Part 2: Refraction In each of the following scenarios, use ray tracing to predict the image distance, determine the actual distance, and find the percent difference.
First, determine the focal length of the double-convex lens:
Scenario 1: Object distance = 50 cm
0
10
30
40
50
60
70
80
90
100
Scenario 2: Object distance = 40 cm
0
20
10
20
30
40
50
60
70
80
90
100
60
70
80
90
100
Scenario 3: Object distance = 30 cm
0
10
20
30
40
50
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___________cm
Week 31
Scenario
Theoretical Image Distance (cm)
Experimental Image Distance (cm)
% Difference
1 2 3 other In Scenarios 1-3, was the image upright or inverted? inverted In Scenarios 1-3, was the image larger or smaller than the object? larger in scenario 2 and 3, smaller in scenario 1 In Scenarios 1-3, was the image real or virtual? real, it was projected onto a screen.
The lens in your eye is shaped like a double convex lens. Do you think the image that hits your retina is upright or inverted? inverted List 3 sources of error in this experiment. Measurement error, imperfections in lens, lens not lined up properly on optics bench.
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Week 32
Week 32 STUDY FOR
QUARTERLY EXAM 4 COVERS LESSONS 23-29
and
LAB ACTIVITIES
130
22-28
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©2010 Digital Interactive Video Education
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DIVE Science-Complete curricula for High School Science: Biology (supplement with any Biology textbook) Chemistry (supplement with any Chemistry textbook) Physics (Saxon Physics® Home Study Kit required)
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Books: The Exchange of Truth, Liberating the World from the Lie of Evolution. ©2007, ISBN 0-595-42177-6 Shormann’s Field Guide to Texas Estuaries, ©2000, ISBN 978-0-9819010-3-9
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