AP Chemistry – Practice Test
Chapters 1-4
Multiple Choice. Draw a circle around the letter that represents the best answer.
CALCULATORS CANNOT BE USED IN THE MULTIPLE CHOICE SECTION
1.
A compound dissolves in water to form an aqueous solution that is a poor conductor of electricity.
The compound may be composed of:
a) a strong acid
b) a strong base
c) a soluble salt
d) covalent molecules
e) ions
2.
Which of the following salts is insoluble in water?
a) Na2S
b) K3PO4
c) Pb(NO3)2 d) Cu(OH)2
3.
e) All of these are soluble in water
Which of the following salts is (are) soluble in water?
I. lead(II) nitrate
II. lead(II) sulfide
III. lead(II) carbonate
a) I only
b) II only
c) III only
d) I and II only
e) I, II and III
4.
Aqueous solutions of sodium sulfide and copper(II) chloride are mixed together. Which statement is
correct?
a) Both NaCl and CuS precipitate from solution.
b) No precipitate forms.
c) CuS will precipitate from solution.
d) NaCl will precipitate from solution.
e) No reaction will occur.
5.
The net ionic equation for the reaction of aqueous sodium hydroxide with aqueous nitric acid is:
a) Na+ + OH– + H+ + NO3–  Na+ + NO3– + H2O
b) Na+ + OH– + H+ + NO3–  NaOH + HNO3
c) H+ + OH–  H2O
d) Na+ + OH–  NaOH
e) None of these
6.
For which one of the following acid solutions will 50.0 mL neutralize 50.0 mL of a 0.2 M Ba(OH)2
solution?
a) 0.1 M HCl
b) 0.2 M HNO3
c) 0.3 M HBr
d) 0.1 M H2SO3
e) 0.2 M H2SO4
7.
When NH3 (aq) is added to Cu2+ (aq), a precipitate initially forms. Its formula is:
a) Cu(NH3)42+
b) Cu(NO3)2
c) Cu(OH)2
d) Cu(NH3)22+
8.
e) CuO
Which of the following are oxidation-reduction reactions?
I.
PCl3 + Cl2  PCl5
II.
Cu + 2 AgNO3  Cu(NO3)2 + 2 Ag
III.
CO2 + 2 LiOH  Li2CO3 + H2O
IV.
FeCl2 + 2 NaOH  Fe(OH)2 + 2 NaCl
a) III
b) IV
c) I and II
d) I, II, and III
e) I, II, III, and IV
9.
Which pair of ions would not be expected to form a precipitate when dilute solutions of each are
mixed?
a) Al3+, S2
b) Pb2+, Cl
c) Ba2+, PO43
d) Pb2+, OH
e) Mg2+, SO42
10. The oxidation state of chromium in K2CrO4 is:
a) –1
b) +3
c) +7
d) +8
e) none of these
11. A piece of metal has a mass of 1.0107 x 10–2 kg. When it was placed in a 100 mL graduated cylinder
containing 30 mL of water, the volume was increased to 32.3 mL. What is the density of the metal
(g/mL), using the correct number of significant figures?
a. 4.4 g/mL
b. 4.4 x 10–3 g/mL
c. 0.313 g/mL d. 4.3943 g/mL
e. 0.337 g/mL
12. What is the number of square decimeters in 6.82 square centimeters?
a. 6.82
b. 0.0682
c. 0.682
d. 68.2
e. 682
13. Rutherford's experiment was important because it showed that:
a. radioactive elements gave off alpha particles
b. gold foil can be made to be only a few atoms thick.
c. a zinc sulfide screen scintillates when struck by a charged particle.
d. the mass of the atom is uniformly distributed throughout the atom.
e. an atom is mostly empty space.
14. Which of the following is NOT the correct chemical formula for the compound named?
a.
b.
c.
d.
e.
calcium phosphate
lithium sulfide
potassium dichromate
potassium nitrate
calcium carbonate
Ca3(PO4)2
Li2S
K2Cr2O7
K2NO3
CaCO3
15. What is the formula of chromium(III)oxide?
a. CrO
b. Cr3O2
c. Cr3O
d. Cr2O3
e. Ch2O3
16. The statement in Dalton's atomic theory that all atoms of the same element are exactly alike has been
replaced in the modern atomic theory because of the discovery of:
a. atoms of the same element with different masses
b. the bending of cathode rays by magnets
c. the electrons and protons in an atom
d. the law of multiple proportions
17. Which of the following formulas is incorrect?
a. Al(OH)3
b. MgCl2
c. K2CrO4
18. The percent calcium (by mass) in calcium fluoride is
a. 51%
b. 40 %
c. 68%
d. (NH4)2PO4
d. 33%
19. How many moles of S8 molecules are there in 80.3 g of sulfur?
a. 0.313 moles
b. 3.20 moles
c. 2.51 moles
d. 0.399 moles
e. none of these
e. 81%
e. Li2CO3
20. Which of the following compounds has the same percent composition by mass as styrene, C8H8?
a. acetylene, C2H2
b. benzene, C6H6
c. cyclobutadiene, C4H4
d. ethyl napthalene, C12H12
e. they all do
21. Consider the element indium, atomic number 49, atomic weight 114.8.
Naturally occurring
indium contains a mixture of indium-112 and indium-115, respectively, in an atom ratio of
approximately
a. 25:75
b. 6 : 94
c. 50 : 50
d. 75 : 25
e. 94 : 6
22. A 6.32 g sample of potassium chlorate was decomposed according to the following equation:
2KClO3 -----> 2KCl + 3O2
How many moles of oxygen are formed?
a. 1.65 g b. 0.051 moles c. 0.0344 moles
d. 0.0774 moles
e. none of these
23. Consider the fermentation reaction of glucose:
yeast
C6H12O6

2C2H5OH + 2CO2
A 1.00 mole sample of C6H12O6 was placed in a vat with 100 g of yeast. If 46 grams of C2H5OH
were obtained, what was the percent yield of C2H5OH?
a. 50%
b. 56%
c. 100%
d. 42%
e. none of these
24. How many grams of H2O will be formed when 32.0 g H2 is mixed with 32.0 g O2 and allowed to
react to form water?
a. 288 g
b. 18.0 g
c. 64.0 g
d. 144 g
e. 36.0 g
25. Which of the following is not the correct chemical formula for the compound named?
a.
b.
c.
d.
e.
ammonium nitrate
sodium sulfite
magnesium oxide
ammonia
copper(II)acetate
NH4NO3
Na2SO3
Mg2O
NH3
Cu(C2H3O2)2
26. Nitrogen boils at -320 ºF. What is this on the Celsius scale?
a. 196 ºC
b. -160 ºC
c. -196 ºC
d. -125 ºC
e. 125 ºC
27. Which of the numbers has the most significant figures?
a. 12.19 x 10-3 g
b. 0.0165 mg c. 923.1 µg d. 2.3440 x 10-6 kg e. 39000 cg
28. Liquid hydrogen is often used to cool samples to cryogenic (very low) temperatures. Its boiling point
is -252.87 ºC. What is its boiling point expressed on the Kelvin scale?
a. -15.14 K
b. 45.28 K
c. 10.28 K
d. 20.28 K
e. 40.13 K
29. The number of protons, neutrons and electrons in
a.
b.
c.
d.
e.
69 p,
56 p,
56 p,
56 p,
56 p,
138
Ba2+ are:
69 n, 67 e
82 n, 54 e
56 n, 56 e
56 n, 54 e
138 n, 82 e
30. Phosphorus has the molecular formula P4 and sulfur has the molecular formula S8. How many grams
of phosphorus contain the same number of molecules as 6.41 g of sulfur?
a. 3.10 g
b. 3.21 g
c. 6.19 g
d. 6.41 g
e. none of these
Free Response:
1.
A 1.25 g sample of a monoprotic acid (one acidic hydrogen per molecule) H"X", requires 61.8 mL
of a 0.250 M NaOH solution for complete titration. Calculate the molar mass of the acid.
2.
For each of the following chemical reactions, assign oxidation numbers, and on that basis, state
whether the reaction is or is not a redox reaction. For any redox reaction, identify the substance
being oxidized, and the substance being reduced.
a)
N2O4

b)
Fe2O3
+ 6H2C2O4 
c)
4NH3
+
NO2
5O2 
2Fe(C2O4)33-
4NO + 6H2O
+ 3H2O
+
6H+
3.
A 4.00 gram sample of an alloy (containing only Ag and Cu) was dissolved in nitric acid. An
excess of NaCl was added to this solution to precipitate all of the Ag out of solution as AgCl. When
the precipitate was dried its mass was determined to be 4.35 grams. Calculate the percentage of Ag
in the alloy.
4. Write the net ionic equations when solutions of each of the following are mixed:
a) nickel(II) nitrate and potassium hydroxide:
b) sodium carbonate and calcium chloride:
c) iron(II) chloride and ammonium phosphate:
5.
What volume of 16.0 M nitric acid is required to prepare 450.0 mL of 0.250 M solution of nitric
acid?
6.
Balance the following redox reaction in "acidic" solution:
Mn2+
7.
+ IO4– 
MnO4–
+
IO3–
Lysine, an essential amino acid (This was "used" in the book Jurassic Park to keep the dinosaurs on
the island), in animals contains C, H, O, and N. In one experiment, the complete combustion of
2.175-g of lysine gave 3.94-g of CO2 and 1.89-g of H2O. In a separate experiment, 1.873-g of
lysine gave 0.436-g of NH3.
a. Calculate the empirical formula of lysine.
b. The approximate molar mass of lysine is 150 g/mol. What is the molecular formula of lysine?