1. Section 9.2 Classifying Chemical Reactions
Classify chemical reactions.
Identify the characteristics of different classes of chemical reactions.
Section 9-2

2. Types of Chemical Reactions
Chemists classify reactions in order to organize the many types.
Synthesis (composition) reaction
a reaction in which two or more substances
react to produce a single product.
Section 9-2

3. Types of Chemical Reactions (cont.)
Combustion reaction
oxygen combines with a substance and
releases energy in the form of heat and light
Heated hydrogen reacts with oxygen to
produce heat and water in a combustion
reaction. This is also a synthesis reaction.
Section 9-2

4. Decomposition Reactions
one in which a single compound breaks down
into two or more elements or new compounds
often require an energy source, such as heat,
light, or electricity, to occur.
Section 9-2

5. Replacement Reactions
Single replacement reaction
a reaction in which the atoms of one element
replace the atoms of another element in a
compound
A + BX → AX + B
Section 9-2

6. Replacement Reactions (cont.)
Double replacement reactions
start with 2 compounds, end up with 2 new
compounds
metals are switching places
Section 9-2

7. Replacement Reactions (cont.)
All double replacement reactions produce
either water, a precipitate, or a gas.
precipitate
solid product produced during a chemical
reaction in a solution
Section 9-2

8. Neutralization
looks like a double replacement reaction
involves an acid and a base as the reactants
you end up with a salt and water

9. Replacement Reactions (cont.)
This table summarizes different ways to predict the products of a chemical reaction.
Section 9-2

10. Replacement Reactions (cont.)
This table shows the steps to write double replacement reactions.
Section 9-2

11. GO TO KAHOOT.IT

12. Replacement Reactions (cont.)
A metal will not always replace a metal in a compound dissolved in water because of differing reactivities.
An activity series can be used to predict if reactions will occur
Halogens frequently replace other halogens in replacement reactions.
Halogens also have different reactivities and do not always replace each other.
Section 9-2

13. A B C D Section 9.3 Assessment
What is the solvent in an aqueous solution?
A. hydrogen
B. sodium ions
C. water
D. alcohol A B C D
Section 9-3

14. A B C D Section 9.3 Assessment
An equation that includes only the particles that participate in a reaction is called:
A. net ionic equation
B. spectator ions
C. complete ionic equation
D. reduced ionic equation A B C D
Section 9-3

15. The law of conservation of mass requires what in a chemical reaction equation?
A. both sides of the equation to contain the same substances
B. the reactants to have the same amount of molecules as the products
C. both sides to have the same amount of atoms of each element
D. the products to have fewer molecules than the reactants A B C D
Chapter Assessment 1

16. A B C D A reaction that gives off heat is what type of reaction?
A. single replacement reaction
B. double replacement reaction
C. synthesis reaction
D. combustion reaction A B C D
Chapter Assessment 2

17. Ions that are present in a solution and do not participate in a chemical reaction when another substance is added are called ____.
A. spectator ions
B. reactants
C. products
D. net ions A B C D
Chapter Assessment 3

18. A double replacement reaction produces all of the following except ____.
A. gases
B. solids
C. light
D. water A B C D
Chapter Assessment 4

19. A B C D What type of reaction is the following?
2H2O(l) + energy → H2(g) + O2(g)
A. synthesis reaction
B. decomposition reaction
C. combustion reaction
D. replacement reaction A B C D
Chapter Assessment 5

20. A B C D What type of reaction is the following?
2H2(g) + O2(g) → 2H2O(l)
A. replacement reaction
B. synthesis
C. combustion reaction
D. double replacement reaction A B C D
STP 1

21. A B C D A precipitate forms in a double replacement reaction only if:
A. the reactivities of the compounds differ
B. the new compound is denser than water
C. the new compound is soluble in water
D. the new compound is not soluble in water A B C D
STP 2

22. A ____ is a statement that uses chemical formulas to show the identities and relative amounts of the substances involved in a chemical reaction.
A. word equation
B. skeleton equation
C. chemical equation
D. balanced equation A B C D
STP 3

23. A B C D Predict the type of reaction. LiBr2 (aq) + 2NaOH (aq) → ____
A. synthesis reaction
B. combustion reaction
C. single replacement reaction
D. double replacement reaction A B C D
STP 4

24. Which reactions are essentially the opposite of synthesis reactions?
A. single-replacement
B. decomposition
C. combustion
D. double-replacement A B C D
STP 5