These problems are to guide your studying for MT II. They do not reflect the style, length,
or hardness of the midterm. Some questions here are harder than the midterm. Only some
of the midterm questions are multiple guess. Answer key (but not solutions) are at end.
9) Ten milliliters of 0.10 M NH3(aq) (K = 1.8 × 10-5) is mixed with 10 mL of 0.10 M NH4Cl. Neglecting
the differences between activities and concentrations, the resulting solution:
A) has a [H+] of approximately 10 -3 M
B) has a pH = 4.74
C) has a [NH4+] greater than that of the NH 4Cl(aq)
D) is acidic
E) has an [OH-] of 1.8 × 10-5 M
9)
10) How will addition of sodium acetate to an acetic acid solution affect the pH?
A) The solution becomes hotter.
B) It will raise the pH.
C) The pH will not change.
D) It will lower the pH.
E) The pH cannot be measured.
10)
13) When 100 mL each of 2.0 × 10-5 M Ca2+ and 2.0 × 10-3 M CO32- are mixed, what is the remaining
Ca2+ ion concentration and is precipitation complete? The solubility product constant of CaCO3 is 2.8
13)
19) A 0.214 M solution of a monoprotic base has a pH of 11.48. What is the ionization constant of this
base?
A) 1.5 × 10-11
19)
× 10-9.
A) 2.8 × 10-6, no
B) 2.8 × 10-6, yes
C) 2.8 × 10-3, no
D) 1.0 × 10-3, no
E) 6.9 × 10-5, no
B) 1.4 × 10-2
C) 2.0 × 10-6
D) 4.3 × 10-5
E) 5.1 × 10-23
27) What is the pH of a 0.250 M solution of formic acid? Ka = 1.8 × 10 -4
A) 8.6
B) 0.60
C) 2.2
D) 5.4
E) 11.8
30) 25 mL of 0.10 M acetic acid is titrated with 0.10 M NaOH. What is the pH after 30 ml of NaOH
have been added? Ka for acetic acid = 1.8 × 10-5.
A) 12.0
B) 12.2
C) 2.0
D) 12.3
E) 8.7
24) For the decomposition of ammonium carbamate
NH4(NH2CO2)(s) ⇌ 2NH3(g) + CO 2(g)
Kp = 0.0596 at a certain temperature. A solid sample of ammonium carbamate is introduced into an
evacuated container and at equilibrium some solid remains in the container. What is the total pressure in
the container?
A) 0.930 atm
B) 1.17 atm
C) 0.179 atm
D) 0.738 atm
1
27)
30)
24)
31) A solution has [HC7H5O2] = 0.100 M and [Ca(C 7H5O2)2] = 0.200 M. Ka = 6.3 × 10 -5 for HC7H5O2.
The solution volume is 5.00 L. What is the pH of this solution after 5.00 ml 10.0 M HCl is added?
A) 4.80
B) 4.70
C) 4.86
D) 4.75
E) 4.65
32)
32) A pH 9.56 buffer was prepared by mixing 2.00 moles of ammonia ( Kb for ammonia is 1.8 × 10-5) and
and 1.00 mol of ammonium chloride in water to form a solution with a volume of 1.00 L. To a 200.0 mL
aliquot of this solution was added 10.0 mL of 10.0 M sodium hydroxide. What was the resulting pH?
A) 9.95
B) 10.50
C) 13.7
D) 9.28
E) 9.56
37) Determine the pH of the following solution. Initial concentrations are given. [HF]
= 1.296 M, [NaF] = 1.045 M, Ka for HF is 6.6 × 10 -4
A) 3.18
B) 3.27
C) 10.73
D) 11.91
37)
E) 3.09
38) What is the minimum pH at which cobalt(II) hydroxide [Ksp = 2.0 × 10 -16] will precipitate from a
solution 0.020 M in CO32+?
A) 7.8
B) 5.8
C) 6.2
D) 7.0
E) 8.2
40) What is the pH of a 0.175 M solution of potassium benzoate? Ka (benzoic acid) = 6.3 × 10-5
A) 8.72
B) 9.10
C) 5.28
D) 3.44
E) 10.56
41) For HClO2, Ka = 1.2 × 10 -2. What is the pH of a solution in which [NaClO2] = 0.193 M and
[HClO2] = 0.203 M?
A) 1.90
B) 3.32
C) 1.92
D) 0.11
E) 1.94
Answer key overleaf
2
40)
Answer Key
1) D
2) D
3) C
4) B
5) A
6) D
7) D
8) A
9) E
10) B
11) A
12) D
13) A
14) D
15) B
16) E
17) C
18) C
19) D
20) A
22) D
23) A
24) D
25) E
26) C
27) C
28) D
29) B
30) A
31) D
32) A
33) D
34) B
35) C
36) C
37) E
38) D
39) A
40) A
41) A
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9) Choose the INCORRECT statement.
A) CH3CH2CH2CH2CH2NH 2 is an amine. B) CH3CH2CH2CH=CH2 is an alkene.
C) CH3CH2CH2CH2CH2OH is an alcohol.
D)
O
||
CH3CH2CH2CH2CH is a ketone.
E) CH3CH2OCH2CH2CH3 is an ether.
4) Which of the following classes of organic compounds and their general structural formulas have been correctly
matched?
I) ester:
IV) Carboxylic acid:
II) Aldehyde:
V) Amide:
III) Ketone:
A) II), IV), and V)
B) II), III), and V)
C) I), II), and V)
D) I), IV), and V)
E) III), IV), and V)
7) Give the name for CH3CH=CHCH3.
A) 3-butene
B) 2-butene
C) 2-butane
D) 2-propene
E) 2-pentene
8) An alcohol of formula C3H8O in which there are only three different kinds of hydrogens is: A) cyclopropanol
B) 2-propanol
C) CH 3CH 2CH 2OH D) ethanol
E) 1-propanol
13) Which of the following compounds is(are) chiral?
A) I
B) II
C) III
D) I + II
15) Give the condensed structural formula for 2-methylpropanoic acid.
A) (CH3) 2CHCH2COOH B) (CH3) 2COOH
C) (CH3)2CHCHO D) CH 3CH 2COOH E) (CH3)2CHCOOH
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E) II + III
5) Which of the following represent two different chair forms of methylcyclohexane?
A)
B)
C)
D)
E)
10) Provide names for compounds A, B and C:
A) A is 3-chloro-4-methylpentanal, B is meta-chlorophenol and C is
3-(2-methylcyclohexyl)cyclopentanecarboxylic acid
B) A is 4-chloro-3-methylpentanal, B is para-chlorophenol and C is
3-(2-methylcyclohexyl)cyclopentanecarboxylic acid
C) A is 3-chloro-4-methylpentanol, B is meta-chlorophenol and C is
3-(2-methylcyclohexyl)cyclopentanecarboxylic acid
D) A is 3-chloro-4-methylpentanal, B is ortho-chlorophenol and C is
3-(3-methylcyclohexyl)cyclopentanecarboxylic acid
E) A is 3-chloro-4-methylpentanon, B is meta-chlorophenol and C is
3-(2-methylcyclohexyl)cyclopentanal
2
12) What is the IUPAC name for the following molecule?
A)
B)
C)
D)
E)
2-bromo-3-methyl-4-propylbutane
2-bromo-3,5-dimethylhexane
2-bromo-4-isopropyl-3-methylbutane
2-bromo-5,5,3-trimethylpentane
3,5-dimethyl-2-bromohexane
16) Name the following compound: CH3CH 2NHCH3.
A) propylamine
B) aminopropane
C) methylaminoethane D) ethylmethylamine E) aminomethylethane
Answer Key
1) B
2) A
3) C
4) D
5) E
6) D
7) B
8) B
9) D
10) A
11) A
12) B
13) B
14) A
15) E
16) D
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