Chewing on Chemistry & Bubble Gum Lab!

Chewing on Chemistry & Bubble Gum Lab! Problem: What do you think is going to happen to the appearance, volume, mass, and density of a sample of bubb...
Author: Antony Simmons
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Chewing on Chemistry & Bubble Gum Lab!

Problem: What do you think is going to happen to the appearance, volume, mass, and density of a sample of bubble gum, if it is chewed for 10 minutes? Background: Read the following to learn about the history of gum. After reading, summarize the information in a short paragraph. Archaeologists have found 2,000 year old chewing gum in Sweden. The ancient Greeks and Mayans chewed various kinds of tree gums. So did the Pilgrims. They picked up the habit from the Native American Indians. The chewing gum we love today can trace its roots (sort of) back to the Battle of the Alamo in 1836! The leader of the Mexican army that overran the Alamo, while the likes of Davy Crockett and Jim Bowie died defending the fort, was General Santa Anna. Everyone knows that part of the story. What is not generally known is that a few years after the war, Santa Anna had left the military and gone into the tree sap business. He was in New York trying to interest American businessmen in buying sapodilla tree sap (an American tropical evergreen tree) from him and then finding a way to refine it into a cheap substitute for rubber! One of the men Santa Anna approached was a New Jersey inventor called Thomas Adams. Adams experimented with the sap, also known as chicle (as in Chiclets!), for some time before giving up in frustration and throwing the stuff out. That might have been the end of the story, however, Adams had a young son who, according to the legend, got in the trash and starting gnawing on the stuff. When Adams discovered his son happily chomping away, he got a great idea! Instead of chewing whale blubber (yummy!) or wax, Adams envisioned a nation chewing Santa Anna’s chicle. Within a year, “Adams New York Snapping and Stretching Gum” was on the market and selling like crazy – especially after it was flavored with sarsaparilla (what folks drank before there was Diet Pepsi). In 1928, Walter Diemer, a Philadelphia accountant, invented bubble gum. Today, the chicle has been replaced by sweetened, flavored, food-grade plastic. That is why, if you swallow your gum, it eventually passes out unchanged out of the body. If you are caught chewing gum in Singapore, you will be fined. If you are caught chewing gum obnoxiously in Fresno, you will be jailed. You will add to the colorful history today as you experiment with bubble gum in the laboratory. Summary:

Hypothesis: What do you think is going to happen to the appearance, volume, mass, and density of gum after you chew it? BE CAREFUL – EACH PERSON IN YOUR GROUP HAS A DIFFERENT PIECE OF GUM! Here is a sample hypothesis: The appearance of the gum will change from a nicely shaped piece of gum to a teeth-marked piece of gum. The mass will increase due to my saliva on the gum. This increase in mass will increase the density of the gum. There will be no change in volume. Make sure you phrase it as a testable statement. Think carefully about this – you will be graded on the quality of your hypothesis!

Materials: Make a list of the materials you are using in this lab.

Procedure: 1. BEFORE CHEWING GUM: Measure all of the characteristics as follows, and record them in your data table 1 below. a. Appearance - write as detailed of a description as possible (texture, color, shape, etc.). b. Mass- use balance. c. Volume- Write down the length, width, and height of your bubble gum below. Calculate the volume of your gum in cm3 using the formula – use cm for your length, width , and height: Volume = length x width x height d. Density- calculate the density in g using the formula: cm3 2. Chew gum for 10 minutes. (No bubble blowing).

Density = mass volume

3. AFTER CHEWING GUM: Measure all characteristics as you did before chewing gum, and record in data table 1 below. a. Appearance- same as above. b. Mass- same as above. c. Volume- measure volume using water displacement, since the gum is now shaped weird! To prevent the gum from sticking to the graduated cylinder, use a string to drop the gum in the graduated cylinder just below the water line. Record the initial and final volumes of the water below, and then subtract the two to get the volume of the gum. d. Density- same as above.

Data: MAKE SURE YOUR DATA HAS UNITS! Type of Gum:

_________________________________________ DATA TABLE 1

Characteristic

Before Chewing

After Chewing

Appearance

Mass lxwxh= Length x width x height = Volume Density = m V

First water volume = Final water volume = Volume of gum =

DATA TABLE 2 Individual in your group

Type of Gum

% Mass Change

YOURSELF

Calculations: Calculate the % change in mass BELOW as a result of chewing the gum. % Mass change = (mass after - mass before) x 100%. mass before Record this in your data table 2 above in the “After Chewing” column.

Graphs: Make THREE BAR GRAPHS – one for mass, one for volume, and one for density comparing the data from before and after chewing, using Logger Pro. Be sure to label your axes properly, title your graph, and use the correct units. See the directions below on how to use Logger Pro. ATTACH YOUR THREE GRAPHS TO THIS LAB. YOUR GRAPHS WILL BE DIFFERENT FROM THE REST OF YOUR GROUP! Share Data/Discussion: Record the % mass change and gum type in data table 2 above for each member of your group. Examine your three bar graphs, and the bar graphs of the members of your group. Also, look at the % mass change for each member of your group. Are the graphs the same? Is the % mass change the same for each member of your group? Why? Discuss this in detail with your group, and answer the conclusion questions below!

LOGGER PRO INSTRUCTIONS

1. Open “Logger Pro” – it is the pink diamond icon at the bottom of the screen. 2. Double click on the graph, and select “Bar Graph”. Then click on the “Axes Options” button, and set the “X Axis” and “Y-Axis” to “Autoscale from 0” under the “Scaling” dropdown menu. 3. Then, hit the “Done” button. 4. Double click on the X button on the data table. This is directly underneath where it says “Data Set”. You can then name the X-axis whatever you want. You do not have to give it a short name, but make sure you put in units. In this lab, we are going to enter in “Bubble Gum” for the name, and leave the units blank. Hit the “Done” button when you are complete. 5. You now want to double click on the Y button on the data table. Follow the same directions as above, entering in whatever values you wish. For this lab, we are going to enter in “Mass” for one graph, “Volume” for the second graph, and “Density” for the third graph for the name. Think about what units you should enter in for each! Make sure you hit the “Done” button when you are complete. 6. Now we are ready to enter our data. In the X column of the data table, enter in your values for X. For this lab, we have two trials or times we measured – before chewing, and after chewing. Enter these words in the first two boxes under where it says “Bubble Gum”. 7. In the Y column, enter in your values for Y. For this lab, this will be the masses for your pieces of gum before and after chewing. 8. You should always title a graph! Double click on the graph. Change the title where it says, “Title”. You should always title a graph Y information vs. X information. So how should we name this graph? Hit the “Done” button when you are complete. 9. Always save your graph on the desktop of the computer in the “Student Folder”. You never know when you will have to go back to fix something! To save a file, go to “File”, and then choose “Save As”. 10. There are three print options under “File”. If you select “Print”, it will just print what is on the screen. If you select” Print Graph”, it will print a large version of the graph, and not the data table. If you select “Print Data Table”, it will just print a large version of the data table. What choice do you want for this lab? 11. Repeat steps 1-10 for your Volume graph and your Density graph. To create a new graph, simply go to “File”, and select “New”.

Conclusions:

1. Look at data table 1, and your bar graph for mass. Did the mass of your gum increase, decrease, or stay the same? Write at least one detailed sentence that explains why this is.

2. Look at data table 1, and your bar graph for volume. Did the volume of your gum increase, decrease, or stay the same? Write at least one detailed sentence that explains why this is.

3. What does a negative % mass change mean? What does a positive % mass change? What did all of your group’s gum types have – a negative or positive % mass change?

4. What type of gum in your group had the greatest negative % mass change? Write at least one detailed sentence that explains why this is.

5. What type of gum in your group had the smallest negative % mass change? Write at least one detailed sentence that explains why this is.

6. Why is it important that we ALL chewed the gum for 10 minutes?

7. Why did we use % mass change instead of a difference in mass (mass after - mass before) to compare our pieces of gum? Write at least one detailed sentence that explains why this is.

8. Look at your bar graph for density. Did the density of your gum increase or decrease? Write one sentence describing how you can tell that the density did this by chewing your gum!

9. What has to happen to the mass of your gum, or to the volume of your gum, for its density to increase?

10. Write one sentence, in your own words, describing what it means for something to be “dense” or to have a large “density”.

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