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Chapter 4 Petrucci 9 ed. © 2007
4
CHEMICAL REACTIONS
CHAPTER OBJECTIVES
1.
Write word equations and symbolic equations for chemical reactions.
2.
Practice chemical nomenclature.
3.
Balance chemical equations by inspection.
4.
Balance “ionic equations” by inspection.
5.
Predict the combustion products—particularly of carbon-hydrogen and carbon-hydrogen-oxygen
compounds—and write a balanced equation.
6.
Predict the products of some simple types of chemical reactions: combination, decomposition,
displacement, and metathesis reactions.
7.
From balanced chemical equations derive conversion factors for use in stoichiometric
calculations.
8.
Solve problems based on balanced chemical equations with quantities given or sought in a variety
of units.
9.
Define the terms associated with solutions, including molarity; compute molarities and solution
volumes.
10.
Solve dilution problems and those involving the mixing of two solutions.
11.
Solve stoichiometry problems when either the reactants or the products are species in solution and
concentration and volume data are given.
12.
Determine the reactant(s) in excess, the limiting reactant, and the amounts of products obtained in
a chemical reaction.
13.
Define the terms actual yield, theoretical yield, and percent yield and compute these quantities for
a given reaction.
14.
Compute the amount of product produced or reactant consumed by two or more simultaneous
reactions.
15.
Compute the amount of product produced by two or more consecutive reactions.
16.
Determine the overall or net reaction for a process consisting of several steps.
Example problems:
1. How many grams of H3PO4 are produced when 20.0 g of HCl are produced by the reaction
below?
PCl5 + 4 H2O  H3PO4 + 5 HCl
2. What is the sum of the coefficients when the reaction below is balanced?
H2SO3 + Al(OH)3  Al2(SO3)3 + H2O
3. If 85.6 mL of a 6.75 M solution is diluted to 6.20 L with water, what is the concentration of
the final solution?
4. 24.0 g of ethane (C2H6) are burned to form CO2 and H2O. How many grams of CO2 are
produced?
5. 42.6 g Cu are combined with 84.0 g of HNO3 according to the unbalanced reaction below.
Which is the limiting reagent and how many grams of Cu(NO3)2 are produced?
Cu + HNO3  Cu(NO3)2 + NO + H2O
Answers:
1. 10.74 g
2. 12
3. 0.093 M
4. 70.3 g
5. HNO3, 125.6 g