Unit 4 Review
1.
Consider the drawings below:
12.
Which of the following statements are true?
I.
The electrons in each molecule tend to be attracted to the
most electronegative element.
II.
Each molecular drawing follows the localized electron
model.
III.
Both HF and CO2 are linear molecules and therefore
non-polar.
IV.
The bond angles of NH3 are slightly less than 109.5o
because the lone pair compresses the angles between the
bonding pairs.
A) I, III, IV
B) I, II, IV
C) I, II, III
D) II, IV
E) All of the above statements (I – IV) are correct.
4.
Which of the following bonds would be the least polar
yet still be considered polar covalent?
A) Mg-O
B) C-O
C) O-O
D) Si-O
E) N-O
13.
Which of the following elements has the lowest
electronegativity?
A) Na
B) Rb
C) Ca
D) S
E) Cl
14.
Which of these elements has the highest
electronegativity?
A) Y
B) I
C) Sb
D) Sr
E) In
15.
Which of the following elements has the lowest
electronegativity?
A) H
B) S
C) Cl
D) Ca
E) Ba
17.
7.
Draw the Lewis structures for the following compounds
to assist you in answering this question.
CBr2H2
BH3
XeCl4
SF4
HCl
Which compound has a see-saw shape?
A) CBr2H2
B) BH3
C) XeCl4
D) SF4
E) HCl
8.
bond?
Which of the following compounds contains an ionic
A)
B)
C)
D)
E)
10.
HCl(g)
NaCl
CCl4
SO2
O2
The most electronegative element of those listed is
A) Rb
B) Cs
C) Fr
D) K
E) Li
The least electronegative element of those listed is
A) O
B) Pb
C) Ba
D) Cu
E) Se
Which of the following contains only non-polar bonds?
A) CH4
B) HCl
C) H2O
D) Mg3N2
E) Cl2
18.
Which of the following has only non-polar covalent
bonds?
A) N2
B) CO
C) HI
D) CCl4
E) NaCl
19.
Order the following bonds from the least polar to the
most polar.
N–O, Ca–O, C–O, O–O, Ni–O
A) O–O < N–O < C–O < Ca–O < Ni–O
B) O–O < C–O < N–O < Ni–O < Ca–O
C) Ca–O < Ni–O < C–O < N–O < O–O
D) O–O < N–O < C–O < Ni–O < Ca–O
E) Ni–O < Ca–O < C–O < N–O < O–O
Unit 4 Review
20.
Which of the following atoms has the greatest
electronegativity?
A) Na
B) Rb
C) Cl
D) Se
33. What is the number of formula units in 0.00300 moles of
Sr(NO3)2?
A. 5.96 X 10 23
B. 6.02 X 10 23
C. 3.00 X 10 21
D. 1.81 X 10 21
23.
If atom X forms a diatomic molecule with itself, the
bond is
A) ionic
B) polar covalent
C) non-polar covalent
D) polar coordinate covalent
E) none of these
34. What is the percent composition of Br in LiBr?
A. 7.99%
B. 43.42%
C. 6.94%
D. 92.01%
27.
When a molecule has a center of positive charge and a
center of negative charge, it is said to have a ______________.
A) magnetic attraction
B) diatomic bond
C) double bond
D) polyatomic ion
E) dipole moment
28.
One of the most important characteristics of the water
molecule is its ______________, which allows it to surround and
attract both positive and negative ions.
A) polarity
B) strength
C) magnetism
D) fluidity
E) stability
29. What is the percent composition of Li in LiBr?
A. 7.99%
B. 6.94%
C. 43.42%
D. 92.01%
30. What is the molecular formula of a compound that has an
empirical formula of C2H4S, and an experimental molar mass of
179?
A. C6H12S3
B. CHS
C. C4H8S2
D. C2H4S
31. What is the percent of oxygen in HNO2?
A. 2.15%
B. 68.06%
C. 14.01%
D. 29.80%
32. What is the molecular formula for a compound that is 64.27%
carbon, 7.19% hydrogen, and 28.54% oxygen, and an
experimental molar mass of 168.19?
A. C12H2O4
B. C9H12O3
C. C3H4O
D. C6H8O2
35. What is the molecular formula for a compound that is 41.39%
carbon, 3.47% hydrogen, and 55.14% oxygen, and an
experimental molar mass of 116.07?
A. C2H2O2
B. C6HO6
C. C4H3O5
D. C4H4O4
36. If a compound is 66.0% barium and 34.0% chlorine, what is
the empirical formula?
A. Ba2Cl
B. Ba3Cl2
C. BaCl2
D. BaCl
37. What is the mass, in grams, of 3.00 moles of SeOBr 2?
A. 764 g
B. 467 g
C. 84.92 g
D. 254.76 g
38. What is the formula mass for C6H3Cl3?
A. 581.64
B. 48.47
C. 181.44
D. 118.44
39. What is the molecular formula of a compound that has an
empirical formula of C2H4O, and an experimental molar mass of
176?
A. C4H8O2
B. C2H4O
C. C8H16O4
D. C6H12O3
40. What is the percent of hydrogen in HNO 2?
A. 68.06%
B. 14.01%
C. 2.15%
D. 29.80%
41. What is the percent of silver in Ag2S?
A. 10.87%
B. 12.94%
C. 87.059%
D. 32.07%
Unit 4 Review
42. What is the empirical formula for a compound that is 60.9%
As and 39.1% S?
A. AsS2
B. AsS
C. As3S2
D. As2S3
43. What is the mass, in grams, of 488 moles of calcium
carbonate?
A. 4.88 X 10 4 g
B. 6.02 X 10 23 g
C. 4.88 X 10 4 g
D. 488 X 10 4 g
E. 160.1 g
44. What is the number of molecules in 0.989 moles of
C6H5NO2?
A. 6.95 X 10 23
B. 5.96 X 10 23
C. 9.89 X 10 23
D. 6.02 X 10 23
45. The mass of one mole of a compound is known as its
A. metric mass
B. unknown mass
C. atomic mass
D. molar mass
46. What is the percent composition of sulfur in Ag2S?
A. 12.94%
B. 87.059%
C. 10.87%
D. 32.07%
47. What is the formula mass for Al2S3?
A. 194.25
B. 145.06
C. 118.08
D. 150.14
48. What is the molecular formula for a compound that is 54.53%
carbon, 9.15% hydrogen, and 36.32% oxygen, and an
experimental molar mass of 88?
A. C5H2O3
B. C10H2O5
C. C4H8O2
D. C4HO2
49. What is the percentage of oxygen in NH4NO3?
A. 5.05%
B. 35.00%
C. 59.96%
D. 14.01%
50. What is the percentage of carbon in C14H10?
A. 94.33%
B. 12.01%
C. 6.50%
D. 5.67%
51. What is the number of formula units in 4.27 moles of WO3?
A. 2.57
B. 4.27
C. 2.57 X 10 24
D. 4.7 X 10 23
52. What is the molecular formula of a compound that has an
empirical formula of C2H2O, and an experimental molar mass of
254?
A. C4H4O2
B. C12H12O6
C. C6H6O3
D. C2H2O
53. What is the mass, in grams, of 6.00 X 10-8 moles of nicotine
(C10H14N2)?
A. 6.02 X 10 23 g
B. 9.74 X 10 -6 g
C. 162.24 g
D. 973.44 g
54. What is the emperical formula for a compound that is 76.89%
Re and 23.12% O?
A. ReO
B. ReO4
C. Re2O7
D. Re7O2
55. In an ionic compound, the chemical formula is generally the
same as the
A. molecular formula
B. molar mass
C. empirical formula
D. formula mass
56. What is the molecular formula of a compound that has an
empirical formula of C2H3O2, and an experimental molar mass of
119?
A. C6H9O6
B. C2H3O2
C. C4H6O4
D. C8H12O8
57. What is the formula mass for B4H10?
A. 53.34
B. 46.14
C. 48.52
D. 57.61
58. A 0.858 g sample of an unknown substance is composed of
0.537 g of copper and 0.321 g of fluorine. What is the empirical
formula?
A. Cu3F2
B. Cu5F3
C. CuF2
D. Cu2F
Unit 4 Review
59. What is the formula mass for Nb5O2?
A. 556.94
B. 659.45
C. 412.08
D. 496.55
64. A 46.25 g sample contains 14.77 g of potasium, 9.06 g of
oxygen, and 22.42 g of tin. What is the empirical formula?
A. KSnO
B. K4Sn2O6
C. K2SnO3
D. KSn2O3
60. A 0.0082 g sample contains 0.0015 g of nickel and 0.0067 g
of iodine. What is the empirical formula?
A. NiI
B. Ni2I3
C. NiI3
D. NiI2
65. What is the percentage of hydrogen in C14H10?
A. 5.67%
B. 94.33%
C. 12.01%
D. 6.50%
61. What is the percentage of nitrogen in NH4NO3?
A. 59.96%
B. 5.05%
C. 14.01%
D. 35.00%
66. What is the percent of nitrogen in HNO2?
A. 68.06%
B. 29.80%
C. 2.15%
D. 14.01%
62. What is the formula mass for Fe2(SO4)3?
A. 688.42
B. 886.24
C. 911.82
D. 399.88
67. What type of formula gives you the simplest whole-number
ratio of atoms in a compound?
A. ideal formula
B. empirical formula
C. molecular formula
D. baby formula
63. What is the formula mass for C2H4?
A. 13.02
B. 28.06
C. 14.02
D. 106.14
68. What is the percentage of hydrogen in NH4NO3?
A. 59.96%
B. 14.01%
C. 35.00%
D. 5.05%
69. What is the number of molecules in 1500 moles of N 2H4?
A. 9.0 X 10 26
B. 6.02 X 10 23
C. 9.0 X 10 23
D. 6.02 X 10 26
29.A
30.A
31.B
32.B
33.D
34.D
35.D
36.C
37.A
38.C
39.C
40.C
41.C
42.D
43.A
44.B
45.D
46.A
47.D
48.C
49.C
50.A
51.C
52.B
53.B
54.C
55.C
56.C
57.A
58.C
59.D
60.D
61.D
62.D
63.B
64.C
65.A
66.B
67.B
68.D
69.A
Answer Key
1.
B
4.
E
7.
D
8.
B
10.
E
12.
C
13.
B
14.
B
15.
E
17.
E
18.
A
19.
D
20.
C
23.
C
27.
E
28.
A
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