Unit 8 Test Review -
ANSWERS
Balance these reactions:
1. 4 LiBr + Co(SO3)2  2 Li2SO3 + CoBr4
2. B2Br6 + 6 HNO3  2 B(NO3)3 + 6 HBr
3. 2 BF3 + 3 Li2SO3  B2(SO3)3 + 6 LiF
Reaction A: From this description, write the word equation, the formula equation, and the
balanced chemical equation: “Potassium bromide plus iron (III) hydroxide react to yield potassium
hydroxide and iron (III) bromide” (what kind of reaction is it?  double replacement)
1.
Write the word equation:
potassium bromide + iron (III) hydroxide  potassium hydroxide + iron (III) bromide
2. Write the formula equation:
KBr + Fe(OH)3  KOH + FeBr3
3. Write the balanced chemical equation:
3 KBr + Fe(OH)3  3 KOH + FeBr3
Reaction B: From this description, write the word equation, the formula equation, and the
balanced chemical equation: “Nitric acid reacts with iron (III) sulfide to produce hydrogen sulfide
plus iron (III) nitrate.” (what kind of reaction is it?  double replacement)
1.
Write the word equation:
Nitric acid + iron (III) sulfide  hydrogen sulfide + iron (III) nitrate
2. Write the formula equation:
HNO3(aq) + Fe2S3  H2S + Fe(NO3)3
3. Write the balanced chemical equation:
6 HNO3(aq) + Fe2S3  3 H2S + 2 Fe(NO3)3
Reaction C:
1. Complete the word equation: (what kind of reaction is it? 
decomposition)
Iron (III) carbonate  iron (III) oxide + carbon dioxide
2. (from part 1, above) Write the formula equation:
Fe2(CO3)3  Fe2O3 + CO2
3. (from part 2, above) Write the balanced chemical equation:
Fe2(CO3)3  Fe2O3 + 3 CO2
Reaction D:
1.
Complete the word equation: (what kind of reaction is it? 
combustion - special case)
Benzene (C6H6) + oxygen  carbon dioxide + water
2.
(from part 1, above) Write the formula equation:
C6H6 + O2  CO2 + H2O
3. (from part 2, above) Write the balanced chemical equation:
2 C6H6 + 15 O2  12 CO2 + 6 H2O
Things to know:
1. Vocabulary: precipitate, subscripts, coefficients, Law of Conservation of Mass, product,
reactant, word equation, formula equation, balanced chemical equation, “replacement”
reactions, synthesis, decomposition, electrolysis, the “seven diatomic elements”, acids,
bases, and activity series (listing in order the activity/reactivity of cations, for instance)
2. What is a “base”?
3. Know how to take a reaction description and convert it to:
a. A word equation, then
b. A formula equation (just get the formulas; equation is not yet balanced)
c. A balanced chemical equation
4. Know how to convert the name of a compound to its formula.
5. Know the five basic types of chemical reactions and their basic form (like “Decomposition is:
AX  A + X”)
6. For a given reaction, recognize which type of the five types it is.
7. Know this special case: what happens when hydrocarbons combust?
8. Know how to name acids:
a. If given a formula, determine the name of the acid
b. If given a name, determine the formula of an acid.
9. Predict what will happen, given only the name(s) of the reactant(s).
a. Complete the word equation;
b. Convert the reactant names to chemical formulas
c. Determine what kind of reaction it is.
d. Figure out what the product(s) will be
e. Balance the chemical equation.
Things to use:
o You will be allowed to use: Your green sheets, a copy of “Reaction Types” and “Activity
Series” (I will give you one of these for the test), and a copy of the Periodic Table to use (I
will give you one)
o You will not need a calculator on this test.
o Bring a pencil (wouldn’t be a bad idea to have a backup pencil).
o Part of the test will be scantron, part written.