AP Chemistry: Summer Assignment
1. By using estimation techniques, determine which of the following is the heaviest and which is the
lightest: a 5-lb bag of potatoes, a 5-kg bag of sugar, or 1 gal of water (assuming the density is
1.0g/mL)?
2. The annual production of sodium hydroxide in the United States in 1999 was 23.2 billion pounds.
(a) How many grams of sodium hydroxide were produced in that year? (b) The density of sodium
hydroxide is 2.130 g/cm3. How many cubic kilometers were produced?
3. In July 1983, an Air Canada Boeing 767 ran out of fuel over central Canada on a trip from
Montreal to Edmonton. (The plane glided safely to a landing at an abandoned airstrip.) The pilots
knew that 22,300 kg of fuel were required for the trip, and they knew that 7682 L of fuel were already
in the tank. The ground crew added 4916 L of fuel, which was only about one fifth of what was
required. The crew members used a factor of 1.77 for the fuel density – the problem is that 1.77 has
units of pounds per liter and not kilograms per liter! What is the fuel density in units of kg/L? What
volume of fuel should have been loaded? (1 lb = 453.6g)
4. Automobile batteries are filled with an aqueous solution of sulfuric acid. What is the mass of the
acid (in grams) in 500. mL of the battery acid solution if the density of the solution is 1.285 g/cm3 and
if the solution is 38.08% sulfuric acid by mass?
5. The density of a single, small crystal can be determined by the flotation method. This method is
based on the idea that if a crystal and a liquid have precisely the same density, the crystal will hand
suspended in the liquid. A crystal that is more dense will sink; one that is less dense will float. If the
crystal neither sinks nor floats, then the density of the crystal equals the density of the liquid.
Generally, mixtures of liquids are used to get the proper density. Chlorocarbons and bromocarbons
(see the list below) are often the liquids of choice. If the two liquids are similar, then the volumes are
usually additive and the density of the mixture relates directly to composition. (An example: 1.0 mL of
CHCl3, d=1.4831 g/mL, and 1.0 mL of CCl4, d=1.5940 g/mL, when mixed, give 2.0mL of a mixture
with a density of 1.5386 g/mL. The density of the mixture is the average of the values of the two
individual components.)
A small crystal of silicon, germanium, tin or lead will hang suspended in a mixture made of 61.18%
(by volume) CHBr3 and 38.82% (by volume) CHCl3. Calculate the density and identify the element.
This will require you to reference the Handbook of Chemistry and Physics.
Density
Liquid
(g/mL)
CH2Cl2
1.3266
CHCl3
1.4832
CCl4
1.5940
CH2Br2
2.4970
CHBr3
2.8899
CBr4
2.9609
6. What is the percent composition of the mineral ilmenite, FeTiO3?
7. Isoprene is a liquid compound that can be polymerized to form natural rubber. It is composed of
88.17% carbon and 11.83% hydrogen. Its molar mass is 68.11 g/mol. What are its empirical and
molecular formulas?
8. If Epsom salt, MgSO4·xH2O is heated to 250°C, all of the water of hydration is lost. On heating a
1.687-g sample of the hydrate, 0.824 g of MgSO4 remains. How many molecules of water occur per
formula unit of MgSO4?
9. Automotive air bags inflate when sodium azide, NaN3, rapidly decomposes to its component
elements:
2NaN3(s) → 2Na(s) + 3N2(g)
How many grams of sodium azide are required to form 6.00 g of nitrogen gas?
10. When benzene (C6H6) reacts with bromine (Br2), bromobenzene (C6H6Br) is obtained:
C6H6 + Br2 → C6H6Br
a. What is the theoretical yield of bromobenzene in this reaction when 30.0 g of benzene reacts with
65.0 g of bromine?
b. If the actual yield of bromobenzene is 56.7 g, what is the percent yield?
11. A strip of zinc metal weighing 2.00 g is placed in an aqueous solution containing 2.50 g of silver
nitrate, causing the following reaction to occur:
Zn(s) + 2AgNO3(aq) → 2Ag(s) + Zn(NO3)2(aq)
a. Which reactant is the limiting?
b. How many grams of silver will form?
c. How many grams of Zn(NO3)2 will form?
d. How many grams of the excess reactant will be left at the end of the reaction?
In addition to working on this problem set, I have provided the links to several on-line practice sets
that will cover information and skills that are considered prerequisites for this course. If you would
like to work ahead, there will be memorization quizzes in the first few weeks of school that will cover
the following information: