Chemistry Test
Learning Assignment (Aqueous Reactions and Thermochemistry) Dr. Podona
Practice for test #2
1.Which of the following is not a strong base?
a) Ca(OH)2
b) KOH
c) NH3
d) LiOH
e) Sr(OH)2
Ans: c
2. Which of the following is paired incorrectly?
a) H2SO4 – strong acid
b) HNO3 – weak acid
c) Ba(OH)2 – strong base
d) HCl – strong acid
e) NH3 – weak base
Ans: b
3. A solid acid HX is mixed with water. Two possible solutions can be obtained. Which of the following is true?
I. II.
a) In case I, HX is acting like a weak acid, and in case II, HX is acting like a strong acid.
b) In case I, HX is acting like a strong acid, and in case II, HX is acting like a weak acid.
c) In both cases, HX is acting like a strong acid.
d) In both cases, HX is acting like a weak acid.
e) HX is not soluble in water.
Ans: b
4. T F ? An acid is a substance that produces OH– ions in water.
Ans: False
5. A 17.0-g sample of HF is dissolved in water to give 2.0 102 mL of solution. The concentration of the solution is:
a) 0.85 M
b) 0.17 M
c) 0.09 M
d) 4.2 M
e) 8.5 M
Ans: d
Learning Assignment (Aqueous Reactions and Thermochemistry) Dr. Podona
63. A mixture of BaCl2 and NaCl is analyzed by precipitating all the barium as BaSO4. After addition of an excess
of Na2SO4 to a 3.743-g sample of the mixture, the mass of precipitate collected is 2.014 g. What is the mass
percentage of barium chloride in the mixture?
a) 60.32%
b) 53.81%
c) 31.65%
d) 48.00%
e) 13.07%
Ans: d
6.. How many grams of NaCl are contained in 350. mL of a 0.334 M solution of sodium chloride?
a) 19.5 g
b) 6.83 g
c) 13.66 g
d) 116.9 g
e) none of these
Ans: b
7. Which of the following aqueous solutions contains the greatest number of ions?
a) 400.0 mL of 0.10 M NaCl
b) 300.0 mL of 0.10 M CaCl2
c) 200.0 mL of 0.10 M FeCl3
d) 200.0 mL of 0.10 M KBr
e) 800.0 mL of 0.10 M sucrose
Ans: b
8. A 30.1-g sample of SrCl2 is dissolved in 112.5 mL of solution. Calculate the molarity of this solution.
a) 21.4 M
b) 1.69 M
c) 42.4 M
d) 0.268 M
e) none of these
Ans: b
9. What mass of solute is contained in 256 mL of a 0.820 M ammonium chloride solution?
a) 11.2 g
b) 171 g
c) 16.7 g
d) 210 g
e) 3.20 g
Ans: a
10. Which of the following do you need to know to be able to calculate the molarity of a salt solution?
I. the mass of salt added
II. the molar mass of the salt
III. the volume of water added
IV. the total volume of the solution
Learning Assignment (Aqueous Reactions and Thermochemistry) Dr. Podona
a) I, III
b) I, II, III
c) II, III
d) I, II, IV
e) You need all of the information.
Ans: d
11. Phosphoric acid, H3PO4, is a triprotic acid. What is the total number of moles of H + available for reaction in
3.50 L of 0.400 M H3PO4?
a) 0.133 mole
b) 1.20 mole
c) 0.467 mole
d) 3.00 moles
e) 4.20 moles
Ans: e
12. The following reactions
2K(s) + Br2(l) → 2KBr(s)
AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3(aq)
HCl(aq) + KOH(aq) → H2O(l) + KCl(aq)
are examples of
a) precipitation reactions
b) redox, precipitation, and acid-base, respectively
c) precipitation (two) and acid-base reactions, respectively
d) redox reactions
e) none of these
Ans: b
13. The following reactions
ZnBr2(aq) + 2AgNO3(aq) → Zn(NO3)2(aq) + 2AgBr(s)
KBr(aq) + AgNO3(aq) → AgBr(s) + KNO3(aq)
are examples of
a) oxidation-reduction reactions
b) acid-base reactions
c) precipitation reactions
d) A and C
e) none of these
Ans: c
14. All of the following reactions
2Al(s) + 3Br2(l) → 2AlBr3(s)
2Ag2O(s) → 4Ag(s) + O2(g)
CH4(l) + 2O2(g) → CO2(g) + 2H2O(g)
can be classified as
Learning Assignment (Aqueous Reactions and Thermochemistry) Dr. Podona
a) oxidation-reduction reactions
b) combustion reactions
c) precipitation reactions
d) A and B
e) A and C
Ans: a
15. Which of the following salts is insoluble in water?
a) Na2S
b) K2CO3
c) Pb(NO3)2
d) CaCl2
e) All of these are soluble in water.
Ans: e
16. Which of the following compounds is soluble in water?
a) Ni(OH)2
b) K3PO4
c) BaSO4
d) CoCO3
e) PbCl2
Ans: b
17. Diabetics often need injections of insulin to help maintain the proper blood glucose levels in their bodies. How
many moles of insulin are needed to make up 45 mL of 0.0059 M insulin solution?
a) 0.00053 mol
b) 0.13 mol
c) 7.6 mol
d) 0.27 mol
e) 0.00027 mol
Ans: e
18. You have equal masses of different solutes dissolved in equal volumes of solution. Which of the solutes would
make the solution having the highest molar concentration?
a) NaOH
b) KCl
c) KOH
d) LiOH
e) all the same
Ans: d
19. Which of the following compounds is soluble in water?
a) Ni(OH)2
b) K3PO4
c) BaSO4
d) CoCO3
e) PbCl2
Ans: b
Learning Assignment (Aqueous Reactions and Thermochemistry) Dr. Podona
20. 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+, PO4 3–
d) Pb2+, OH–
e) Mg2+, SO4 2–
Ans: e
21. In writing the complete ionic equation for the reaction (if any) that occurs when aqueous solutions of KOH
and Mg(NO3)2 are mixed, which of the following would not be written as ionic species?
a) KOH
b) Mg(NO3)2
c) Mg(OH)2
d) KNO3
e) All of the above would be written as ionic species.
Ans: c
22. The net ionic equation for the reaction of calcium bromide and sodium phosphate contains which of the
following species?
a) 2Br–(aq)
b) PO4 3–(aq)
c) 2Ca3(PO4)2(s)
d) 6NaBr(aq)
e) 3Ca2+(aq)
Ans: e
23. When sodium chloride and lead(II) nitrate react in an aqueous solution, which of the following terms will be
present in the balanced molecular equation?
a) PbCl(s)
b) Pb2Cl(s)
c) NaNO3(aq)
d) 2NaNO3(aq)
e) 2PbCl2(s)
Ans: d
24. What mass of NaOH is required to react exactly with 25.0 mL of 3.0 M H2SO4?
a) 3.0 g
b) 0.7 g
c) 6.0 g
d) 150 g
e) none of these
Ans: c
25. A student weighs out 0.681 g of KHP (molar mass = 204.22 g/mol) and titrates to the equivalence point with
36.78 mL of a stock NaOH solution. What is the concentration of the stock NaOH solution? KHP is an acid
with one acidic proton.
a) 0.00333 M
b) 0.123 M
c) 0.0185 M
d) 0.0907 M
e) none of these
Ans: d
Learning Assignment (Aqueous Reactions and Thermochemistry) Dr. Podona
26. In which of the following does nitrogen have an oxidation state of +4?
a) HNO3
b) NO2
c) N2O
d) NH4Cl
e) NaNO2
Ans: b
27. The oxidation state of iodine in IO3 – is:
a) 0
b) +3
c) –3
d) +5
e) –5
Ans: d
28. In the reaction 2Ca(s) + O2(g) → 2CaO(s), which species is oxidized?
a) O2
b) O2–
c) Ca
d) Ca2+
e) none of these
Ans: c
29. Balance the following equation: KI + HNO3 → KNO3 + NO + I2 + H2O
Ans: 6KI + 8HNO3 → 6KNO3 + 2NO + 3I2 + 4H2O
30. How much heat is required to raise the temperature of a 4.48-g sample of iron (specific heat = 0.450 J/g°C)
from 25.0°C to 79.8°C?
a) 1.98 J
b) 246 J
c) 546 J
d) 661 J
e) 110 J
Ans: e
31. A 18.3 g piece of aluminum (which has a molar heat capacity of 24.03 J/°C·mol) is heated to 82.4°C and
dropped into a calorimeter containing water (specific heat capacity of water is 4.18 J/g°C) initially at 22.3°C.
The final temperature of the water is 25.8°C. Ignoring significant figures, calculate the mass of water in the
calorimeter.
a) 63.1 g
b) 1.70 kg
c) 1.91 g
d) 923 g
e) none of these
Ans: a
Learning Assignment (Aqueous Reactions and Thermochemistry) Dr. Podona
32. Consider the reaction
H2(g) + 1 2 O2(g) → H2O(l) H° = –286 kJ
Which of the following is true?
a) The reaction is exothermic.
b) The reaction is endothermic.
c) The enthalpy of the products is less than that of the reactants.
d) Heat is absorbed by the system.
e) Both A and C are true.
Ans: e
33. What is the specific heat capacity of a metal if it requires 178.6 J to change the temperature of 15.0 g of the
metal from 25.00°C to 32.50°C?
a) 0.630 J/g°C
b) 11.9 J/g°C
c) 23.8 J/g°C
d) 1.59 J/g°C
e) 291 J/g°C
Ans: d
34. A 140.0-g sample of water at 25.0°C is mixed with 106.1 g of a certain metal at 100.0°C. After thermal
equilibrium is established, the (final) temperature of the mixture is 29.6°C. What is the specific heat capacity
of the metal, assuming it is constant over the temperature range concerned?
a) 0.36 J/g°C
b) 0.72 J/g°C
c) 0.21 J/g°C
d) 2.8 J/g°C
e) none of these
Ans: a
35. Calculate H° for the reaction C4H4(g) + 2H2(g) → C4H8(g), using the following data:
H°combustion for C4H4(g) = –2341 kJ/mol
H°combustion for H2(g) = –286 kJ/mol
H°combustion for C4H8(g) = –2755 kJ/mol
a) –128 kJ
b) –158 kJ
c) 128 kJ
d) 158 kJ
e) none of these
Ans: b
36. Given:
Cu2O(s) + 1 2 O2(g) → 2CuO(s) H° = –144 kJ
Cu2O(s) → Cu(s) + CuO(s) H° = +11 kJ
Calculate the standard enthalpy of formation of CuO(s).
Learning Assignment (Aqueous Reactions and Thermochemistry) Dr. Podona
a) –166 kJ
b) –299 kJ
c) +299 kJ
d) +155 kJ
e) –155 kJ
Ans: e
37. An unknown substance dissolves readily in water but not in benzene (a nonpolar solvent). Molecules of what
type are present in the substance?
a) neither polar nor nonpolar
b) polar
c) either polar or nonpolar
d) nonpolar
e) none of these
Ans: b
38. A 30.1-g sample of SrCl2 is dissolved in 112.5 mL of solution. Calculate the molarity of this solution.
a) 21.4 M
b) 1.69 M
c) 42.4 M
d) 0.268 M
e) none of these
Ans: b
39. You mix 265.0 mL of 1.20 M lead(II) nitrate with 300.0 mL of 1.55 M potassium iodide. The lead(II) iodide is
insoluble. Which of the following is false?
a) The final concentration of Pb2+ ions is 0.151 M.
b) You form 107 g of lead(II) iodide.
c) The final concentration of K+ is 0.823 M.
d) The final concentration of NO3 – is 0.823 M.
e) All are true.
Ans: d
40. A mixture of BaCl2 and NaCl is analyzed by precipitating all the barium as BaSO4. After addition of an excess
of Na2SO4 to a 3.743-g sample of the mixture, the mass of precipitate collected is 2.014 g. What is the mass
percentage of barium chloride in the mixture?
a) 60.32%
b) 53.81%
c) 31.65%
d) 48.00%
e) 13.07%
Ans: d