CHAPTER 9
Chemical Reactions
9.1 Reactions and Equations
Practice Problems
1. Write a word equation and a skeleton equation for each of the following descriptions of
chemical reactions.
a. Solid lithium reacts with chlorine gas to produce solid lithium chloride.
b. Nitrogen gas reacts with oxygen gas to produce nitrogen dioxide gas.
c. Solid iron reacts with aqueous copper(II) nitrate to produce solid copper and aqueous
iron(II) nitrate.
Practice Problems
2. Write a balanced chemical equation for the following reactions, making sure coefficients are in
their lowest possible ratio.
a. Solid potassium reacts with liquid water to produce hydrogen gas and a water solution of
potassium hydroxide.
b. Calcium chloride and sodium carbonate in water solution produce solid calcium carbonate
and a water solution of sodium chloride.
c. Liquid bromine and solid lithium iodide react to form solid lithium bromide and solid
iodine.
9.2 Classifying Chemical Reactions
Practice Problems
3. Identify each of the following skeleton equations as representing a synthesis reaction, a
combustion reaction, both synthesis and combustion, or decomposition reaction. Balance each
equation if necessary.
a. N2(g) + H2(g)  NH3(g)
b. CaCO3(s)  CaO(s) + O2(g)
c. Se(s) + O2(g)  SeO3(g)
d. C2H4(g) + O2(g)  CO2(g) + H2O(g)
Practice Problems
4. Predict whether a single-replacement reaction will occur between the following pairs of
possible reactants. If so, write a balanced chemical equation for the reaction.
a. chlorine gas and aqueous potassium iodide
b. magnesium metal and aqueous copper(II) sulfate
c. copper metal and iron(III) chloride in water solution
d. lead metal and aqueous silver nitrate
Practice Problems
5. Write a balanced chemical equation for each of the following double-replacement reactions.
a. A water solution of zinc bromide (ZnBr2) and a water solution of potassium hydroxide form
a water solution of potassium bromide and a precipitate of zinc hydroxide.
b. A water solution of copper(II) sulfate and a water solution of barium chloride produce a
water solution of copper(II) chloride and solid barium sulfate.
c. A precipitate of iron(III) carbonate and a water solution of sodium nitrate are formed when
a water solution of iron(III) nitrate and a water solution of sodium carbonate are mixed.
9.3 Reactions in Aqueous Solutions
Practice Problems
6. Write balanced chemical, complete ionic, and net ionic equations for each of the following
reactions.
a. Aqueous solutions of lead(II) nitrate and ammonium chloride are mixed, forming a
precipitate of lead(II) chloride.
b. Aqueous solutions of aluminum chloride and sodium carbonate are combined, producing
solid aluminum carbonate.
Practice Problems
7. Write balanced chemical, complete ionic, and net ionic equations for the reactions between the
following substances, which produce water.
a. nitric acid (HNO3) and aqueous barium hydroxide
b. sulfuric acid (H2SO4) and aqueous sodium hydroxide
c. phosphoric acid (H3PO4) and aqueous lithium hydroxide
Practice Problems
8. Write balanced chemical, complete ionic, and net ionic equations for the reactions between the
following substances, which produce a gas.
a. hydrochloric acid and aqueous sodium cyanide, with production of hydrogen cyanide gas
(HCN)
b. sulfuric acid (H2SO4) and aqueous rubidium sulfide, with production of hydrogen sulfide gas
Chapter 9 Review
9. Define chemical reaction. Where are the reactants and products shown in an equation for a
chemical reaction, and how are the physical states indicated?
10. Compare and contrast word equations, skeleton equations, and balanced chemical equations.
11. Briefly list the steps used in balancing a chemical equation.
12. Contrast synthesis, combustion, and decomposition reactions.
13. Contrast single-replacement and double-replacement reactions.
14. Define aqueous solution. What name is given to a solid that forms when two aqueous solutions
are mixed?
15. How do complete ionic and net ionic equations differ?
16. Name three typical types of products that may be formed in double-replacement reactions.