AP Chemistry 2-Day Review Sheet Test 2B
Chang Chapters 1, 2, 3, 4abc, 5, 6
Name
1. Calculate the density of fluroine gas measured at STP, in grams per liter.
2. Find the number of moles and the number of molecules in 15.0 grams of ethanol, C2H5OH.
3. What volume of 2.0 M CaCl2 solution contains 37 grams of CaCl2? What is the concentration of
calcium ion? Chloride ion?
4. Give the nuclear symbol of an atom which contains 47 protons, 46 electrons, and 60 neutrons.
5. Give the formulas of the following ionic compounds. Then, circle those which are soluble.
a. copper (II) sulfate pentahydrate
b. iron (III) acetate
c. cobalt (III) phosphate
6. Determine the simplest (empirical) formula of a compound of carbon, hydrogen and chlorine in which
the mass percent of C is 23.8% and that of H is 5.94%. If the molar mass of the substance is 101, what
is its molecular formula?
7. Consider the reaction:
2 Fe + 3 Cl2  2 FeCl3
What is the theoretical yield of FeCl3, starting with 22.00 gram of Fe and 72.00 g of Cl2?
8. Combustion of a 10.00 gram sample of a compound containing the three elements C, H and Cl gives
13.64 grams of CO2 and 7.05 gram of water. What are the mass percents of C, H and Cl in the
compound? Find the empirical formula of the compound.
9. Write molecular, complete ionic and net ionic equations for various reactions.
a) sodium chlorate dissolves in water
b) sodium sulfide solution is mixed with zinc nitrate
c) a piece of zinc is placed in to a solution of copper(II) sulfate
10. 42.6 mL of 0.253 M magnesium nitrate is mixed with 22.6 mL of 0.135 M sodium phosphate.
a. Write molecular, complete ionic and net ionic equations for this reaction.
b. Calculate the amount of precipitate formed by the reaction.
c. Which reactant is limiting? In excess?
11. Calculate the molarity of a solution.
1. Calculate the molarity of 250. mL of a solution containing 62.2 grams of iron(III) nitrate. What is the
molarity of iron(III) ions in the solution? Molarity of nitrate ions in the solution?
2. 275 mL of 0.100 M Na2S solution is diluted to a final volume of 500. mL. What is the molarity of the
solution? Molarity of sodium ions? Sulfide ions?
12. Balance the following oxidation-reduction reaction. Identify the substance oxidized, the substance reduced,
the oxidizing agent, and the reducing agent:
Cr2O72- + NO2- → Cr3+ + NO3- (in acidic solution)
13. Which of the following reactions will be spontaneous at room temperature? (Use a table of “Standard
Reduction Potentials”.)
a) Ag + Mg2+  Ag+ + Mg
b) Mg + Cu2+  Mg2+ + Cu
c) H+ + Mg  Mg2+ + H2
14. Convert each of the following to atmospheres:
a) 500 mmHg
b) 500 kPa
d) 8000 torr
15. What volume would 19 grams of fluorine gas occupy at STP?
16. Vinegar, which contains acetic acid, reacts with chalk (calcium carbonate) according to the following
equation:
2 HC2H3O2 + CaCO3  2 NaC2H3O2 + CO2 + H2O
How many mL of 3.0 M acetic acid are needed to react with an excess of calcium carbonate in order to produce
55 liters of carbon dioxide, measured at 27C and 742 mmHg?
17. 8.0 grams of hydrogen and 10.0 grams of argon are placed in a 6.2 liter rigid container at 32C.
a) Calculate the total pressure in the container.
b) Calculate the mole fractions of hydrogen and argon.
c) Calculate the partial pressures of each gas in the container.
18. Consider the following gases, all measured at STP:
He, Ne, Xe
a. Which of the gases has the greatest kinetic energy?
b. Which of the gases has the greatest root mean square velocity?
c. In order to have the same velocity as helium, would krypton gas need to have a higher, lower, or the
same temperature?
d. An unknown gas effuses at 4 times the rate as Xenon at STP. What is the molecular mass of the
unknown gas?
20. Nitrogen and hydrogen gases react to produce ammonia gas, according to the following equation:
N2 + 3 H2  2 NH3
If 27 liters of nitrogen gas and 54 liters of hydrogen gas react completely, what volume of ammonia gas
would be produced? Assume all gases are measured at STP.
21. Consider the combustion of methanol, CH3OH (or CH4O).
a) Write a balanced equation for the equation.
b) Find H for the reaction using a table of Hf values.
c) If 1.55 gram of methanol is burned in a calorimeter, calculate H for the reaction.
d) Assuming that the 2.00 L of water in the calorimeter absorbed all of the heat from part “c”, what
temperature change did the water experience?