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Unit 3: Chemical Reactions
Title
Introduction • The study of substances and their reactions • Processes have a role in almost every aspect of everyday life • Key to developing new products & solutions to problems
• Learning about chemistry involves... o Mixing substances in test tubes o Researching specific topics o Applying and extending knowledge
• As you learn about chemical processes, you will become more aware of the ways that chemistry‐related issues affect people's lives
Intro Chemistry
5.1
Classification of Matter (anything that occupies space)
Pure Substances
Mixtures
(all particles are the same)
(2+ pure substances)
Elements
Solutions
2+ elements bonded together
1 type of atom
1 visible component
Heterogeneous Mixtures 2+ visible components
Compounds
Matter
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1. Chemical Reactions printable Slides part One.notebook
February 21, 2017
Classification of Matter Pure Substance • All the particles that make up the substance are the same; the substance has constant properties. Elements Cannot be broken down into different types of atoms; they only contain one type of atom (ex. gold). Represented by a chemical symbol (ex. Au). Compounds Contain two or more different elements (different types of atoms) bonded together in a fixed proportion. Identified by chemical formulas (ex. H2O).
Pure Substances
Classification of Matter Mixtures • Contain two or more pure substances that can be separated by physical means.
Homogeneous Mixtures Have only one visible component. A.k.a. solutions. Not easily separated.
Heterogeneous Mixtures Contain two or more visible components. A.k.a. mechanical mixtures. Easier to separate by filtration, evaporation of the solvent, and by using ones hands to remove individual components.
Mixtures
Properties of Matter • A physical property is a characteristic of a substance o o o o
state color odor hardness
Baking soda:
o o o o
mass luster texture ductility
o o o o
volume density solubility viscosity
o o o o
malleability crystal form melting point boiling point
white; crystalline solid @ room temp; dissolves in water to form a solution Water: tasteless & odorless; liquid at standard atmospheric temperatures and pressures; very slightly blue, colourless in small quantities; boiling point = 100oC
o A physical change is a change in the size or form of a substance, and it does not change the chemical properties of the substance.
Physical Property
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Properties of Matter • A chemical property is a characteristic behavior that occurs when a substance changes to a new substance Ex: reacts with acid, reacts with water, combusts
o
The change itself is called a chemical change. A substance is changed into one or more new substances (ex: burning, cooking, and rusting)
Chemical Property
p. 175
Practice Questions
1. Classify each of the following as a pure substance or a mixture. Explain your choices. a) soapy water b) hydrogen gas c) sodium chloride
2. Classify each as an element or a compound. Explain your choices. a) hydrogen b) potassium carbonate c) water d) Mg
3. Draw separate sketches to represent substances made up of 10 particles of each of the following: a) an element b) a compound c) a mixture
4. Classify each of the following as a physical property or a chemical property. Explain your choices. a) gasoline is a clear, pink solution b) gasoline burns in air c) water boils at 100oC d) electric current can split water into hydrogen and oxygen gas
p. 175 #14
Chemical Reactions
New colour
• Clues of chemical change:
Bubbles
Precipitate
Difficult/impossible to reverse
Heat or light
Chemical Reactions
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1. Chemical Reactions printable Slides part One.notebook
February 21, 2017
Chemical Reactions • Chemical reactions have a standard format when written: Reactants
Products
A+ B
C + D
• Chemical reactions can be used to make new substances and are also useful for identifying unknown substances (ex. testing for different gases). Acid + Limestone = CO2 gas
Chemical Reactions
p. 175
Practice Questions
5. When aluminum metal is added to hydrobromic acid, hydrogen gas and an aluminum bromide solution are formed. a) Was this a chemical or a physical change? Explain. b) Which substances are reactants and which are products? 6.
In your own words, describe the chemical tests that can be used to identify the following gases: a) hydrogen b) oxygen c) carbon dioxide d) water vapour
7. When sodium carbonate is added to water, it dissolves. When hydrochloric acid is added to the solution, the solution fizzes. What kinds of changes occurred? Explain. 8. (a) Why does a glowing splint (piece of wood) burst into flame when oxygen gas is tested? (b) When you test for hydrogen gas, another gas is involved. What is this other gas?
p. 175 #58
Periodic Table of Elements • Helps to explain and predict both chemical and physical properties of different elements. • It is a means of organizing all of the elements. • Elements that are within the same column of the periodic table are called chemical families or groups. • Rows of the periodic table are called chemical periods.
Groups or Families
Periods
Periodic Table
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Periodic Table of Elements o
Metals are toward the left side of the table and are located below the staircase. ‐ Tend to be shiny and malleable solids that are conductors of heat and electricity.
o
Nonmetals are toward the right side of the table, above the staircase. ‐ Tend to be dull and brittle. They are found to be solids, liquids, and gases, all of which are insulators.
o
Metals and nonmetals located directly above and below the staircase that exhibit metallic and nonmetallic properties. These elements are also often referred to as metalloids.
PT Metals
18
1
NONMETALS
2
4
Halogens
3
5
Noble Gases
Alkali Metals
Alkaline Earth Metals
METALLOIDS
METALS
Nov 68:21 PM
Periodic Table of Elements o
There are four key families and each tends to have the same physical and chemical properties. ‐ Alkali metals – Group 1 ‐ Alkaline Earth metals – Group 2 ‐ Halogens – Group 17 ‐ Noble Gases – Group 18
o
Hydrogen is unique because it exhibits properties of both metals and nonmetals. It is located above group one because it has one valence electron just like the alkali metals.
PT Families
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Atomic Structure • The Bohr‐Rutherford Model of the atom o Shows that atoms are composed of three subatomic particles:
Atomic Structure
Atomic Structure Protons are heavy and positively charged. Neutrons have approximately the same mass as protons, but they are neutral. Electrons have almost no mass and they are negatively charged. Protons and neutrons are located at the dense core of the atom (the nucleus).
# + = # ‐
Atoms are electrically neutral because they have the same number of protons and electrons.
Atomic Structure
Nov 84:40 PM
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Atomic Structure o
The atomic number of an element indicates the number of protons it has in one atom.
____ protons ____ neutrons ____ electrons ____ amu
o
____ protons ____ neutrons ____ electrons ____ amu
____ protons ____ neutrons ____ electrons ____ amu
The atomic weight of an atom indicates the sum of protons and neutrons. ‐ It is measured in atomic mass units (amu).
Atomic # & Weight
Atomic Structure o
o
The model represents the arrangement of electrons. Electrons orbit the nucleus at different energy levels (aka orbits or shells) ‐ 1st shell: 2 electrons 2nd ‐ 4th shells: 8 electrons each
‐
The farther away an electron is from its nucleus, the greater its energy and its tendency to be involved in chemical reactions.
‐
Electrons in the outer‐most shell (valence shell) are called valence electrons; they are involved in bonding.
This theory only applies to elements up to 20 electrons.
Energy Levels
Atomic Structure • Noble gases (Family 18) have full orbits o they don't have any spare electrons they're willing to share, nor do they need to borrow from others o this is why they don't tend to react with other elements
Noble Gases Electrons
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Atomic Notation
Atomic Notation
Atomic Structure Draw Bohr Diagrams for the following elements: Name:
Hydrogen Helium Lithium Beryllium
Symbol:
____________ _________ _________ _____________
Atomic #:
____________ _________ _________ _____________
Protons:
____________ _________ _________ _____________
Electrons:
____________ _________ _________ _____________
Diagram:
Nov 1010:24 AM
5.1
Classification of Matter (anything that occupies space)
Pure Substances
Mixtures
(all particles are the same)
(2+ pure substances)
Elements
Solutions
2+ elements bonded together
1 type of atom
1 visible component
Heterogeneous Mixtures 2+ visible components
Compounds
Compounds
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Compounds
• 2+ different elements bonded in a fixed proportion • Atoms want an arrangement of electrons like the nearest noble gas • Bonding shares/transfers electrons to become more stable
• This is called the octet rule. o Noble gases do not easily form compounds because their electron arrangements are stable.
Octet Rule
Compounds
• There are three types of compounds: o Ionic – Electrons are transferred between metals and nonmetals o Molecular – Electrons are shared between nonmetals. o Metallic – electrons move freely around metals.
NaCl
Mg2Sn
CO2
H2 O
KF
Fe3C
• A binary compound is simply a compound that consists of atoms only two different elements (ex. NaCl, SO3, CaS).
Types of Compounds
Compounds • A chemical formula is a combination of symbols that represent a particular compound. It indicates… o what elements are present, and o the number of each atom present
NaCl: CO2 : H2O: Mg2Sn: KF: Fe3C:
___ sodium, ___ chlorine ___ carbon, ___ oxygen ___ hydrogen, ___ oxygen ___ magnesium, ___ tin ___ potassium, ___ flourine ___ iron, ___ carbon
Chemical Formula
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Compounds • Atoms become ions when they gain or donate valence electrons. o ionic charge is the # value of the charge (+/‐). o It is written as a superscript on the right of the symbol (ex. Ba2+). o Names of nonmetal ions end with “ide” (ex. F‐ is the fluoride ion). o Families tend to form ions with similar charges.
(Anion)
(Cation)
Atom to Ion
p. 189 #1‐4 1. (a) How do metals form ionic compounds with nonmetals? (b) Describe the process with an example.
2.
Beryllium and fluorine react to form an ionic compound. (a) Which element is the metal and which is the nonmetal? (b) Draw Bohr diagrams of beryllium and fluorine. (c) How many electrons must each element gain or lose to form stable ions? (d) Draw sketches to show how this compound forms by transfer of electrons. (e) Indicate the ionic charges on the ions. (f) What is the overall charge on the compound? (g) What is the chemical formula of the compound?
3. Repeat question 2 for the compound formed by aluminum and fluorine.
4. What part of the atom is involved in making chemical bonds?
p. 189 #14
Ionic Compounds • Made up of a cation (metal) and an anion (nonmetal) because electrons were transferred from the metal to the nonmetal.
‐1
+1
Characteristics
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Ionic Compounds • Opposite charges attract, so opposing charges of the two ions cause them to be attracted to each other. o Ionic Bonding: force of attraction b/t oppositely charged ions. o Result = electrically neutral compound o Examples:
NaCl
1 Na+ ion,
1 Cl‐ ion
CaF2
1 Ca2+ ion,
2 F‐ ions
Ionic Bonding
Ionic Compounds • A solid ionic compound (ionic solid) is also known as a salt o it is a solid consisting of oppositely charged ions. Sodium Chloride Copper Sulfate NaCl CuSO 4
Potassium Dichromate K2Cr2O7
Mercury Sulfide HgS
Salts
Ionic Compounds ‐ FORMULA WRITING 1. 2. 3.
Temporarily write the ionic charge above each symbol. Crisscross the ionic charges, using them as subscripts for the opposite ions. Reduce the subscripts to the lowest numbers possible.
Calcium Phosphide
Formula Writing
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Ionic Compounds ‐ FORMULA WRITING o
NOTE… § There are no spaces between symbols when writing chemical formulas. § Be sure to capitalize the first letter of a chemical symbol. If there is a second letter, it is always lowercase. § There is no need to write a subscript if there is only one atom of that element present.
BaCl2 Notes
Ionic Compounds ‐ FORMULA WRITING
Practice
p. 195 #2, 3, 5 2. Draw a Bohr diagram to show the electron transfer that occurs when magnesium (Mg) and fluorine (F) form the compound magnesium fluoride.
3. Write the formulas for the compounds formed by the following combinations of elements: a) lithium and fluorine b) calcium and bromine c) sodium and nitrogen d) aluminum and nitrogen 5. Write the formulas for the following compounds: a) sodium iodide b) beryllium fluoride c) magnesium oxide d) aluminum sulfide
p. 195 #2,3,5
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Ionic Compounds ‐ NAMING • IUPAC: non‐governmental agency that is the recognized authority in developing standards for the naming of the chemical elements and their compounds
International http://www.iupac.org/ Union of Pure and Applied Chemistry • When naming, all letters should be lower‐case
Naming
Ionic Compounds ‐ NAMING • Naming binary ionic compounds: o Write the name of the metal followed by the name of the nonmetal ending in “ide”
NaCl sodium chloride
CaF2 calcium fluoride K2O potassium oxide
Binary Ionic Compounds
p. 195 #1‐9 1. (a) How does the sum of the charges on the positive ions compare to the sum of the charges on the negative ions in ionic compounds?
(b) Calculate the sum of the ionic charges in the compound Al2O3. Show your work.
4. Name each of the compounds formed by the following combinations of elements: (a) lithium & fluorine lithium fluoride (b) calcium & bromine calcium bromide (c) sodium & nitrogen sodium nitride (d) aluminum & nitrogen aluminum nitride
6. Write the names for the following compounds: (a) KCl potassium chloride (b) Na3P sodium phosphide (c) CaF2 calcium fluoride
p. 195 #1, 4, 6
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Ionic Compounds ‐ NAMING o
o
Some metals can form more than one kind of ion – they are called polyvalent metals. Begin by writing the name of the metal and add a Roman numeral in round brackets after it to indicate its ionic charge. Finish with the name of the nonmetal ending in “ide”.
Fe3N2
iron (II) nitride
Polyvalent Ionic Compounds
p. 195 #7,8,9 7. Write the formulas for the following compounds:
(a) copper(I) bromide
(b) copper(II) bromide
(c) iron(II) sulfide
8. Write the names for the following compounds:
(a) SnCl2
(b) SnCl4
(c) PbBr2
9. Write the formula and name of the compound formed by each of the following combinations of ions. (Some need Roman Numerals)
(a) Fe3+ & O2‐
(b) Ca2+ & F‐
(c) Cu+ & S2‐
p. 195 #79
Ionic Compounds ‐ NAMING o
Polyatomic ion: atoms that tend to stay together and carry an overall ionic charge (ex. Nitrate ion: NO3‐).
Polyatomic Ionic Compounds
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Ionic Compounds ‐ NAMING o
o
When writing the formula of a polyatomic ionic compound, add brackets around the ion before showing the number you need. § Ex. Ba(NO3)2 – barium nitrate Write the name of the metal first, then the polyatomic ion's name.
Fe(NO3)3
Pb(SO4)2
Polyatomic Ionic Compounds
p. 198 #1‐4 1. In your own words, explain what is meant by "polyatomic ion." Give two examples. 2. What happens to the ions in the compound sodium nitrate when it dissolves in water? 3. Write the formulas for the following compounds: (a) sodium phosphate (b) calcium sulfate (c) potassium chlorate (d) aluminum hydroxide (e) beryllium nitrate (f) magnesium hydrogen carbonate (g) nickel carbonate 4. Write the names for the following compounds: (a) K2CO3 (b) Na2SO4 (c) Al(HCO3)3 (d) AgNO3
p. 198 #14
Ionic Compounds ‐ NAMING o
Acids form when hydrogen atoms combine with certain ions § The hydrogen ion has an ionic charge of 1+ (H+). § Acids have the subscript aq (aqueous) after their formula.
o
To name acids, follow these simple guidelines: H + ______ate = ____ic acid H + ______ite = ____ous acid H + element = hydro____ic acid
o
H2SO4 = sulfuric acid H2SO3 = sulfurous acid HCl = hydrochloric acid
An oxyacid is simply and acid formed when H+ combines with polyatomic ions that contain oxygen.
Acids
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Flow Chart for Ionic Compounds Ionic Compounds (metal + nonmetal)
Formula Writing
Naming
(given the name)
(given the formula)
Criss‐cross the ionic charges & reduce if needed
"metal nonmetal+ide" Polyvalent Metals What do you do?
Polyatomic Ions What do you do?
Acids What do you do? What do you do?
Ionic Compounds Flow Chart
Molecular Compounds
• Most of the compounds encountered each day do not contain ions. • They contain neutral groups of atoms called molecules. o Molecule: a molecular compound • Molecular compounds are made of nonmetals that are sharing electrons.
Molecular Compounds
Molecular Compounds • A covalent bond is a shared pair of electrons held between two nonmetal atoms. The nonmetals are held together to form a molecule.
• Diatomic Molecules are elements that exist naturally as molecules made of two atoms. o H2, N2, O2, F2 , Cl2, Br2, I2 are all diatomic.
Molecular Compounds
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Molecular Compounds “Start at 7, make a 7, and don’t forget the hat!”
Diatomic Molecules
Molecular Compounds Add the second atom to form each
diatomic molecule of the group of 7
Diatomic Molecules
Molecular Compounds • The number of electrons that nonmetals need to share to become stable is a clue to the number of covalent bonds it can form.
• The combining capacity (aka bonding capacity) is a measure of the number of covalent bonds that a nonmetal needs to form a stable molecule. • Use the crisscross method and reduce the subscripts if possible.
Combining Capacities of Nonmetal Atoms
4
3
2
C Si
N P As
O S Se
1 H F Cl Br I
Formulas
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Molecular Compounds Carbon & sulfur
4
3
2
C Si
N P As
O S Se
Step 1: Write the left‐most element first
February 21, 2017
1 H F Cl Br I
Step 2: Write the combining capacities above the element symbols
Step 3: Crisscross the combining capacities to get subscripts
Step 4: Reduce the subscripts if possible
Step 5: Remove any "1" subscripts ‐ they're not needed
Formulas
Molecular Compounds
• Four of the many exceptions to naming rules: water (H2O) ammonia (NH3) hydrogen peroxide (H2O2) methane (CH4) • Prefixes are used to differentiate between molecules. The prefixes indicate the number of atoms present. ‐
4 = tetra
5 = penta 8 = octa
3 = tri
2 = di
1 = mono
7 = hepta
6 = hexa
9 = nona
10 = deca
• If there is only one atom of the first element listed, the prefix MONO is not needed.
Naming Molecules
p. 204 # 1, 2, 5, 6 1. How can you tell the difference between ionic compounds and molecular compounds? 2. a) What kinds of atoms form molecular compounds? b) How do the atoms in molecular compounds form stable electron configurations? c) What type of bond holds atoms together in molecules? 5. Name the following compounds, using prefixes: d) SiCl4 c) OF2 b) NI3 a) CBr4 6. Write chemical formulas for and name the molecular compounds forms by the following pairs of elements. b) nitrogen & hydrogen a) silion & oxygen d) sulfur & bromine c) phosphorus & chlorine f) carbon & chlorine e) oxygen & fluorine
p. 204 #1,2,5,6
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Organic Compounds • Organic compounds are molecular compounds that contain carbon atoms as the “backbone” of the structure.
• The simplest organic molecule is methane (CH4) because it only has one carbon.
• Many naturally occurring organic compounds come from plants (ex. carbohydrates such as cellulose, starch, glucose, etc.).
Organic Compounds
Organic Compounds • Hydrocarbons are organic compounds that are made of hydrogen and carbon only and are found in various combinations. o A mixture of hydrocarbons makes up fossil fuels like oil and natural gas.
Hydrocarbons
p. 207 #1‐5 1. a) What are organic compounds? b) What are the most common elements present in organic compounds? c) What is the combining capacity of carbon? d) Why is carbon called the backbone of organic molecules? 2. What are two sources of different kinds of organic compounds? 3. a) What elements are present in hydrocarbon molecules? b) How are hydrocarbons produced naturally? 4. a) What is meant by the term "fossil fuel"? b) Name three examples of fossil fuels. 5. Give five uses for natural gas and petroleum products.
p. 207 #15
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Table 1. Measuring Masses in a Chemical Reaction Total Mass (g) (reactants and apparatus )
PREDICTION (g)
Total Mass (g)
(mass of products (products and and apparatus) apparatus )
QUALITATIVE observations of reactants and products iron (III) chloride
sodium hydroxide iron (III) hydroxide Qualitative observations of reaction
sodium chloride
Mar 1010:14 AM
Chemical Reactions ‐ EQUATIONS
• The Law of Conservation of Mass states that, in a chemical reaction, the total mass of the reactants (starting materials) is always equal to the total mass of the products (the materials produced).
MASS OF REACTANTS = MASS OF PRODUCTS o
Example:
o
Total mass =
o
What would happen if a gas was produced?
methane + oxygen à water + carbon dioxide
10g total mass = 10 g total mass
Conservation of Mass
Chemical Reactions ‐ EQUATIONS
• A word equation is a chemical reaction represented by the names of the substances involved; it indicates what reacts and what is produced.
copper + silver nitrate à silver + copper (II) nitrate
o o o
Left side = reactants; Right side = products An arrow points from the reactants toward the products Each reactant and each product is separated by a plus (+) sign
Word Equation
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Chemical Reactions ‐ EQUATIONS • A skeleton equation is a chemical reaction represented by formulas of the reactants instead of the chemical names. copper + silver nitrate à silver + copper (II) nitrate Cu + AgNO3 à Ag + CuNO3 iron + oxygen à iron(III) oxide zinc + hydrochloric acid à hydrogen + zinc chloride hydrogen + oxygen à water vapour
Skeleton Equation
p. 219 #2‐4 2. Examine the following word equation: propane + oxygen à carbon dioxide + water a) List all the reactants in this reaction
b) List all the products in this reaction
c) What is the purpose of the arrow in the word equation?
3. Write word equations for the following reactions: a) CaCl2 and Na2SO4 react to form CaSO4 and NaCl
b) BaCO3 reacts when heated to produce BaO and CO2
c) AgNO3 reacts with KCl to produce AgCl and KNO3
4. Write word equations to represent the following chemical reactions: a) Carbon dioxide and water are produced in human cell respiration. The reactants are sugar and an important gas that humans need to survive.
b) Stalactites form in caves when calcium bicarbonate reacts to form calcium carbonate, water, and carbon dioxide gas.
p. 219 #24
Chemical Reactions ‐ EQUATIONS • A balanced chemical equation is a skeleton equation with coefficients in front of certain reactants and/or products to ensure that there are an equal number of atoms of each type on each side of the arrow.
CH4 + 2O2 à 2H2O + CO2
Balanced Equation
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Chemical Reactions ‐ EQUATIONS • Steps to writing balanced chemical equations:
iron + oxygen à iron oxide 1.
Write the skeleton equation
Fe + O2 à Fe3O4 2.
Count the # of atoms of each type in reactants & products Products 3 4
Reactants 1 2
Atom Fe O
3. Multiply each of the formulas by the appropriate coefficients to balance the number of atoms.
3Fe + 2O2 à Fe3O4
Chemical Equations
Apr 141:46 PM
p. 229 #2,3 2. Copy the following skeleton equations into your notebook, then balance the equations. b) K + O2 à K2O a) Na + Cl2 à NaCl
c) H2 + O2 à H2O
d) H2 + Cl2 à HCl
e) N2 + H2 à NH3
f) CO + O2 à CO2
g) Al + Br2 à AlBr3
h) N2H4 + O2 à H2O + N2
i) CH4 + O2 à CO2 + H2O
3. For each of the following, write the correct skeleton equation, and then balance it to form a chemical equation: a) copper(II) oxide + hydrogen à copper + water b) lead(II) nitrate + potassium iodide lead(II) iodide + potassium nitrate
c) calcium + water à calcium hydroxide + hydrogen gas
d) lead(II) sulfide + oxygen à lead + sulfur dioxide
e) hydrogen sulfide à hydrogen + sulfur
p. 229 #23
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Chemical Reactions ‐ TYPES
• There are five main types of chemical reactions:
Combustion fuel + oxygen oxides + energy
Decomposition
Synthesis A
B
AB
AB
Single Displacement A
BC
B AC
A
B
Double Displacement AB CD
AC BD
Types of Reactions
Chemical Reactions ‐ TYPES
• There are five main types of chemical reactions:
Combustion
the explosive relationship
Decomposition
Synthesis the hook‐up
the break‐up
Single Displacement
Double Displacement
the other man/woman
the full switcheroo
Types of Reactions
Chemical Reactions ‐ TYPES 1.
Combustion Reaction § Often called burning , it is the very rapid reaction of a substance with oxygen to produce oxides. § Energy is produced, mainly in the form of heat and light. § NOTE: When hydrocarbons burn (i.e. react with oxygen) they always produce carbon dioxide & water. § When oxygen is a reactant and the products are carbon dioxide and water, it is a combustion reaction. § Example: C3H8 + 5O2 à 3CO2 + 4H20
Combustion
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Chemical Reactions ‐ TYPES 2.
Synthesis Reaction § Also called formation reactions. § Two or more smaller compounds combine to form a larger compound (ex. A + B à AB). H2 + O2 à H2O § Example: (balanced chemical equation: 2H2 + O2 à 2H2O) CO2 + H2O à H2CO3 (aq) § Example:
Synthesis
Chemical Reactions ‐ TYPES 3.
Decomposition Reaction § Opposite of synthesis reactions. § A larger compound decomposes into elements or smaller compounds (ex. AB à A + B). H2O à H2 + O2 § Example: (balanced chemical equation: 2H2O à 2H2 + O2) 2NI3 à N2 + 3I2 § Example: NH4NO3 à N2O + 2H2O § Example:
Decomposition
Chemical Reactions ‐ TYPES 4.
Single Displacement Reaction § One element displaces or replaces another element in a compound. § A cation will only switch with the other cation, or an anion will only switch with the other anion. A' + AB à A + A'B § Example: B' + AB à B + AB' Mg + 2AgNO3 à 2Ag + Mg(NO3)2 § Example: Br2 + CaI2 à I2 + CaBr2 § Example:
Single Displacement
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Chemical Reactions ‐ TYPES 5.
Double Displacement Reaction § Different elements displace each other or exchange places to form two new compounds. § The cations will pair up with the anions of the other compounds. AB + A'B' à AB' + A'B § Example: Pb(NO3)2 + 2KI à PbI2 + 2KNO3 § Example:
Double Displacement
p. 247 #1‐5 1.
What do synthesis and single displacement reactions have in common?
2.
What do decomposition and double displacement reactions have in common?
3.
Which two types of reactions seem to be opposites?
4.
Identify each of the following reactions as one of the types of reactions: a) barium + sulfur à barium sulfide
b) bromine + sodium iodide à iodine + sodium bromine
c) barium nitrate + sodium sulfide à barium sulfide + sodium nitrate
d) lithium carbonate à carbon dioxide + lithium oxide
e) lead(II) oxide à lead + oxygen f) calcium + water à hydrogen + calcium hydroxide g) sulfur trioxide + water à sulfuric acid 5.
Write skeleton and balanced chemical equations for each of the reactions in question 4.
p. 247 15
Jan 282:41 PM
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