Chemistry 141 Exam I
Fall 2010: Chapters 1, 2 & 3 (through 3.4): Brown, Lemay, Bursten, Murphy
Name (print legibly) ______Blue Key________
Student ID Number____________________________
There is a periodic table and a section of miscellaneous information at the end of this exam.
Circle the best answer choice for each question on this test form as well as on the scantron sheet.
NO PROGRAMABLE CALCULATORS WILL BE ALLOWED FOR THIS EXAM.
1.
(2 points) Which of the following set of characteristics best describes a liquid:
a. definite volume and definite shape
b. no definite volume and definite shape
c. no definite shape and definite volume
d. no definite shape and no definite volume
2.
(2 points) Which of the following is a pure substance.
a. tea
d. sugar water
3.
b. a casserole
c. carbon monoxide
e. pomegranate juice
(3 points) Two or more substances that can be mixed in varying proportions, where the
composition is constant throughout are:
a. a compound
b. an element
d. a homogeneous mixture
4.
c. a heterogeneous mixture
e. a crystalline solid
(4 points) Determine the mass of an object that has a volume of 88.6 mL and a density of
9.77 g/mL.
a. 298 g
b. 1100 g
c. 907 g
d. 568 g
e. 866 g
88.6 mL ⋅
Fusion - B
9.77g
= 866 g
mL
1
5.
(4 points) Complete the following calculation and report the answer to the correct
number of significant figures. (965.43 x 3.911) + 9413.4136
c. 1.32 x 104
a. 13189
b. 13189.2
d. 1.3 x 104
e. 1.3129 x 104
965.43 x 3.911 = 3776 4 significant figures
3776
+ 9413.4136
13189.
6.
Answer can only be known to the ones place
(4 points) A student weighed 30.00 μg of sulfur in the lab. This is the same mass as:
a. 3.000 x 10-8 g
30.00 μg ⋅
7.
b. 3.000 x 10-5 kg
c. 3.000 x 10-5 mg
d. 3.000 x 104 ng
10 -6 g 1 ng
⋅
= 3.00E4 ng
μg 10 -9 g
(5 points) A fishing boat accidently spills 3.0 barrels of diesel oil into the ocean. Each
barrel contains 42 gallons. If the oil film on the ocean is 2.5 x 102 nm thick, how many
square meters will the oil slick cover?
a. 1.9 x 10-3 m2
b. 1.9 x 106 m2
c. 1.9 x 107 m2
V = thickness ⋅ width ⋅ length
d. none of these
thickness = V
thickness
3
42 gal 4 qts
1L
10 3 cm 3 ⎛ 1m ⎞
3
V = 3 barrells ⋅
⋅
⋅
⋅
⋅⎜ 2
⎟ = 4.77E − 1 m
barrell gal 1.0567 qt
L
10
cm
⎝
⎠
3
4.77E - 1 m
thickness =
= 1.9E6 m 2
1m
2
2.5E2 nm ⋅ 9
10 nm
Fusion - B
2
8.
(3 points) Accuracy refers to?
a. how close a measured number is to zero
b. how close a measured number is to the calculated value
c. how close a measured number is to other numbers
d. how close a measured number is to the true value
e. how close a measured number is to infinity
9.
(3 points) Which one of the following has the element name and symbol correctly
matched?
a. S, sodium
10.
b. Tn, tin
c. Fe, iron
d. N, neon
e. B, bromine
(5 points) The recommended adult dose of ElixophyllinTM, a drug used to treat asthma, is
6.00 mg/kg of body mass. Calculate the dose in milligrams for a 115-lb person.
1lb = 453.59 g
a. 24
b. 1521
c. 1.5
d. 313
e. 3.1 x 105
115 lb ⋅
0.45359 kg 6.00 mg
⋅
= 313 mg
lb
kg
11. (3 points) Which statement below correctly describes the responses of alpha, beta, and
gamma radiation to an electric field?
a. Both beta and gamma are deflected in the same direction, while alpha shows no
response.
b. Both alpha and gamma are deflected in the same direction, while beta shows no
response.
c. Both alpha and beta are deflected in the same direction, while gamma shows no
response.
d. Alpha and beta are deflected in opposite directions, while gamma shows no
response.
e. Only alpha is deflected, while beta and gamma show no response.
Fusion - B
3
12.
(3 points) The element __________ is the most similar to strontium in chemical and
physical properties.
a. Li
b. At
c. Rb
e. Cs
d. Ba
13. (3 points) Elements in Group 7A (17) are known as the __________.
a. chalcogens
b. alkali metals
d. halogens
e. noble gases
c. alkaline earth metals
14. (3 points) All atoms of a given element have the same __________.
a. mass
d. number of electrons and neutrons
15.
c. number of neutrons
b. number of protons
e. density
(3 points) Isotopes are atoms that have the same number of __________ but differing
number of __________.
16.
a. protons, electrons
b. neutrons, protons
d. electrons, protons
e. neutrons, electrons
(3 points) Which one of the following is most likely to lose electrons when forming an
ion?
a. F
17.
c. protons, neutrons
b. P
c. Rh
d. S
e. N
(5 points) The average atomic mass of lithium is 6.941 amu. Lithium has two naturally
occurring isotopes, 6Li (7.52%) and 7Li (92.48%). The mass of 6Li is 6.0151 amu. What is
the mass of 7Li?
a. 7.016 amu
b. 0.926 amu
c. 6.001 amu
d. 7.000 amu
6.941 = (6.0151)(0.0752) + (?)( 0.9248)
Fusion - B
4
18. (3 points) TiO2 is a white oxide used in paints. What is the proper name for TiO2?
a. titanium oxide
c. titanic acid
b. titanium (IV) oxide
d. titanium oxoate
19. (3 points) What is the proper name for Co(ClO4)3?
a. cobalt trichlorotetroxide
b. cobalt (II) chlorate
c. cobaltous chlorate
d. cobalt (III) perchlorate
20. (3 points) Aqua regia is a mixture of hydrochloric acid and nitric acid that is capable of
dissolving gold. What are the formulas of its components?
b. HClO4, HNO3
a. HClO, HNO4
d. HCl, HNO3
c. HCl, HNO2
21.
22.
(2 points) The processes of _____________ and ______________ both move the neutronproton ratio in the same direction.
a. beta decay & electron capture
b. alpha decay & electron capture
c. electron capture & positron emission
d. beta & alpha decay
(3 points) Which of the following products correctly completes the following nuclear
reaction?
232
a.
234
Pa
Th
+ 2 01 n → ???
b.
234
+
U
0
1-
e
c.
236
U
d.
232
Ac
Pa + 2 01 n → 234
+ 10- e
92 U
(2 points) As the atomic number (Z) increases past element 20 the neutron-proton ratio
________________________.
232
91
23.
a. decreases
Fusion - B
b. is one-to-one
c. does not change
d. increases
5
24.
(2 points) How many hydrogen atoms are there on each side of the following balanced
equation?
Al2Si2O5(OH)4(s) + 6 H+(aq) Æ 2 Al3+(aq) + 2 H4SiO4(aq) + H2O(l)
b. 4
a. 10
25.
c. 6
d. 8
e. 9
(2 points) Which of the following is a decomposition reaction?
a. 4 Al(s) + 3 O2(g) Æ 2 Al2O3(s)
b. CH4(g) + 2 O2(g) Æ CO2(g) + 2 H2O(g)
c. SrCO3(s) Æ SrO(s) + CO2(g)
d. 2 Mg(s) + O2(g) Æ 2 MgO(s)
26.
(3 points) What are the correct coefficients for the complete combustion of pentane
(C5H12) to carbon dioxide and water?
__ C5H12(g) + __ O2(g) Æ ___ CO2(g) + __ H2O(g)
a. 1, 8, 5, 6
27.
d. 1, 16, 5, 12
c. 75.53
b. 199.89
d. 110.98
(3 points) The percent by mass of Al in aluminum carbonate is _______________.
a. 23.1
Al 2 (CO 3 )3
29.
c. 1, 4.5, 5, 7
(3 points) The formula weight (amu) of Calcium bromide is _______________.
a. 119.98
28.
b. 2, 9, 5, 6
b. 11.5
c. 31.0
d. 49.0
2 ⋅ 26.98 amu
⋅ 100 = 23.1%
(2 ⋅ 26.98 + 3 ⋅ 12.01 + 9 ⋅ 16.00)
(3 points) Avogadro’s number of elementary particles is equal to which of the following?
a. The number of O atoms in 15.994 grams of oxygen
b. The number of H2 molecules in exactly 1 m3 of hydrogen.
c. The number of C atoms in exactly 12 grams of carbon-12
d. The number of water molecules in exactly 1 gram of H2O
Fusion - B
6
30.
(2 points) The units of molar mass are ____________________.
b. g/cm3
a. L/s
31.
(4 points) How many moles of propane (C3H8; FW 44.097) are there in 135.7 g?
a. 0.3250
135.7g ⋅
32.
b. 5.984E3
c. 3.077
d. 1.671E-4
1 mol
= 3.077 mol
44.097 g
(4 points) How many molecules are there in 16.2 g of the insecticide Lindane (C6H6Cl6;
FW 290.81)?
a. 3.35E22
16.2 g ⋅
33.
d. molecules/m3
c. g/mol
b. 2.98E-23
c. 2.84E27
d. 3.52E-28
1 mol 6.0221E23 molecules
⋅
= 3.35E22 molecules
290.81 g
mol
(0 points) What is your Chmy 141, College Chemistry I, section?
a. Sec. 1 (10 AM)
b. Sec. 2 (11 AM)
c. Sec. 3 (8 AM)
34. Extra Credit – 5 points
What is the empirical formula of a compound with the following percent composition by
mass; 32.79% Na, 13.02% Al, and 54.19% F?
a. NaAl2F4
c. Na2Al2F3
b. Na3AlF6
1mol
= 1.426 mol
23.0 g
1 mol
13.02g ⋅
= 0.4822 mol
27.0 g
1 mol
54.19 g ⋅
= 2.852 mol
19.0 g
Na 1.426 Al 0.4822 F2.852
d. Na5Al2F8
32.79 g ⋅
Fusion - B
Na 3 AlF6
7
Useful Formulae and Constants °F = °C(9 /5) + 32.0
Avogadro’s Number 6.0221 x 1023 mol-1 ; 1 inch = 2.54 cm
1 m = 102cm
1 L = 1.0567 qt 1 lb = 453.6 g
1 pm = 10-12 m
12 in = 1 ft
1 mi = 1.609 km = 5280 ft volume = l ⋅ w ⋅ h
1 nm = 10-9 m
FW = formula weight
1.6605402E-27 kg amu-1
1 gal = 4 qt
Fusion - B
8
Chemistry 141 Exam I
Fall 2010: Chapters 1, 2 & 3 (through 3.4): Brown, Lemay, Bursten, Murphy
Name (print legibly) ___White Key________
Student ID Number____________________________
There is a periodic table and a section of miscellaneous information at the end of this exam.
Circle the best answer choice for each question on this test form as well as on the scantron sheet.
NO PROGRAMABLE CALCULATORS WILL BE ALLOWED FOR THIS EXAM.
1.
(2 points) Which of the following is a pure substance.
b. a casserole
a. carbon monoxide
d. sugar water
2.
c. tea
e. pomegranate juice
(3 points) Two or more substances that can be mixed in varying proportions, where the
composition is constant throughout are:
a. a compound
b. an element
d. a heterogeneous mixture
3.
c. a homogeneous mixture
e. a crystalline solid
(4 points) Complete the following calculation and report the answer to the correct
number of significant figures. (965.43 x 3.911) + 9413.4136
a. 1.3129 x 104
b. 13189.2
d. 1.3 x 104
e. 13189
c. 1.32 x 104
965.43 x 3.911 = 3776 4 significant figures
3776
+ 9413.4136 Answer can only be known to the ones place
13189.
4.
(4 points) A student weighed 30.00 μg of sulfur in the lab. This is the same mass as:
a. 3.000 x 10-8 g
b. 3.000 x 10-5 kg
c. 3.000 x 10-5 mg
d. 3.000 x 104 ng
10 -6 g 1 ng
30.00 μg ⋅
⋅
= 3.00E4 ng
μg 10 -9 g
Fission - A
1
5.
(5 points) A fishing boat accidently spills 3.0 barrels of diesel oil into the ocean. Each
barrel contains 42 gallons. If the oil film on the ocean is 2.5 x 102 nm thick, how many
square meters will the oil slick cover?
a. 1.9 x 10-3 m2
b. 1.9 x 106 m2
c. 1.9 x 107 m2
d. none of these
V = thickness ⋅ width ⋅ length
thickness = V
3
6.
thickness
3
3
42 gal 4 qts
1L
10 cm ⎛ 1m ⎞
3
V = 3 barrells ⋅
⋅
⋅
⋅
⋅⎜ 2
⎟ = 4.77E − 1 m
barrell gal 1.0567 qt
L
10
cm
⎠
⎝
3
4.77E - 1 m
thickness =
= 1.9E6 m 2
1
m
2.5E2 nm 2 ⋅ 9
10 nm
(3 points) Accuracy refers to?
a. how close a measured number is to zero
b. how close a measured number is to the calculated value
c. how close a measured number is to other numbers
d. how close a measured number is to the true value
e. how close a measured number is to infinity
7.
(3 points) Which one of the following has the element name and symbol correctly
matched?
a. S, sodium
8.
b. Tn, tin
c. B, bromine
d. N, neon
e. Fe, iron
(5 points) The recommended adult dose of ElixophyllinTM, a drug used to treat asthma, is
6.00 mg/kg of body mass. Calculate the dose in milligrams for a 115-lb person.
1lb = 453.59 g
a. 313
b. 1521
c. 1.5
d. 24
e. 3.1 x 105
115 lb ⋅
Fission - A
0.45359 kg 6.00 mg
⋅
= 313 mg
lb
kg
2
9.
(2 points) Which of the following set of characteristics best describes a liquid:
a. definite volume and no definite shape
b. no definite volume and no definite shape
c. definite shape and no definite volume
d. no definite shape and no definite volume
10.
(4 points) Determine the mass of an object that has a volume of 88.6 mL and a density of
9.77 g/mL.
b. 866 g
c. 907 g
d. 568 g
e. 1100 g
a. 298 g
88.6 mL ⋅
9.77g
= 866 g
mL
11. (3 points) Which statement below correctly describes the responses of alpha, beta, and
gamma radiation to an electric field?
a. Both beta and gamma are deflected in the same direction, while alpha shows no
response.
b. Alpha and beta are deflected in opposite directions, while gamma shows no
response.
c. Both alpha and beta are deflected in the same direction, while gamma shows no
response.
d. Both alpha and gamma are deflected in the same direction, while beta shows no
response
e. Only alpha is deflected, while beta and gamma show no response.
12. (3 points) The element __________ is the most similar to strontium in chemical and
physical properties.
a. Li
b. At
c. Cs
d. Ba
e. Rb
13. (3 points) Elements in Group 7A (17) are known as the __________.
a. halogens
b. alkali metals
d. chalcogens
e. noble gases
Fission - A
c. alkaline earth metals
3
14. (3 points) All atoms of a given element have the same __________.
a. mass
b. number of electrons and neutrons
e. density
d. number of protons
15.
c. number of neutrons
(3 points) Isotopes are atoms that have the same number of __________ but differing
number of __________.
16.
a. protons, electrons
b. neutrons, protons
d. electrons, protons
e. neutrons, electrons
c. protons, neutrons
(3 points) Which one of the following is most likely to lose electrons when forming an
ion?
a. Rh
b. P
c. F
d. S
e. N
17. (5 points) The average atomic mass of lithium is 6.941 amu. Lithium has two naturally
occurring isotopes, 6Li (7.52%) and 7Li (92.48%). The mass of 6Li is 6.0151 amu. What is
the mass of 7Li?
a. 7.000 amu
b. 0.926 amu
c. 6.001 amu
d. 7.016 amu
6.941 = (6.0151)(0.0752) + (?)(0.9248)
Fission - A
4
18. (3 points) TiO2 is a white oxide used in paints. What is the proper name for TiO2?
a. titanium (IV) oxide
b. titanium oxide
c. titanic acid
d. titanium oxoate
19. (3 points) What is the proper name for Co(ClO4)3?
a. cobalt trichlorotetroxide
b. cobalt (III) perchlorate
c. cobaltous chlorate
d. cobalt (II) chlorate
20. (3 points) Aqua regia is a mixture of hydrochloric acid and nitric acid that is capable of
dissolving gold. What are the formulas of its components?
a. HClO, HNO4
b. HClO4, HNO3
c. HCl, HNO2
d. HCl, HNO3
21.
22.
(2 points) The processes of _____________ and ______________ both move the neutronproton ratio in the same direction.
a. beta decay & electron capture
b. alpha decay & electron capture
c. electron capture & positron emission
d. beta & alpha decay
(3 points) Which of the following products correctly completes the following nuclear
reaction?
232
a.
234
Pa
+ 2 01 n → ???
Th
b.
236
+
U
0
1-
e
c.
234
U
d.
232
Ac
Pa + 2 01 n → 234
+ 10- e
92 U
(2 points) As the atomic number (Z) increases past element 20 the neutron-proton ratio
________________________.
232
91
23.
a. increases
Fission - A
b. is one-to-one
c. does not change
d. decreases
5
24.
(2 points) How many hydrogen atoms are there on each side of the following balanced
equation?
Al2Si2O5(OH)4(s) + 6 H+(aq) Æ 2 Al3+(aq) + 2 H4SiO4(aq) + H2O(l)
a. 8
25.
b. 4
c. 6
e. 9
d. 10
(2 points) Which of the following is a decomposition reaction?
a. 4 Al(s) + 3 O2(g) Æ 2 Al2O3(s)
b. CH4(g) + 2 O2(g) Æ CO2(g) + 2 H2O(g)
c. SrCO3(s) Æ SrO(s) + CO2(g)
d. 2 Mg(s) + O2(g) Æ 2 MgO(s)
26.
(3 points) What are the correct coefficients for the complete combustion of pentane
(C5H12) to carbon dioxide and water?
__ C5H12(g) + __ O2(g) Æ ___ CO2(g) + __ H2O(g)
a. 1, 4.5, 5, 7 b. 2, 9, 5, 6
27.
(3 points) The formula weight (amu) of Calcium bromide is _______________.
a. 119.98
28.
d. 1, 16, 5, 12
c. 1, 8, 5, 6
b. 199.89
c. 75.53
d. 110.98
(3 points) The percent by mass of Al in aluminum carbonate is _______________.
a. 23.1
b. 11.5
c. 31.0
d. 49.0
2 ⋅ 26.98 amu
⋅ 100 = 23.1%
(2 ⋅ 26.98 + 3 ⋅ 12.01 + 9 ⋅ 16.00)
(3 points) Avogadro’s number of elementary particles is equal to which of the following?
Al 2 (CO 3 )3
29.
a. The number of C atoms in exactly 12 grams of carbon-12
b. The number of H2 molecules in exactly 1 m3 of hydrogen.
c. The number of O atoms in 15.994 grams of oxygen
d. The number of water molecules in exactly 1 gram of H2O
Fission - A
6
30.
(2 points) The units of molar mass are ____________________.
b. g/cm3
a. g/mol
31.
(4 points) How many moles of propane (C3H8; FW 44.097) are there in 135.7 g?
b. 5.984E3
a. 3.077
135.7g ⋅
32.
c. 0.3250
d. 1.671E-4
1 mol
= 3.077 mol
44.097 g
(4 points) How many molecules are there in 16.2 g of the insecticide Lindane (C6H6Cl6;
FW 290.81)?
a. 3.52E-28
16.2 g ⋅
33.
d. molecules/m3
c. L/s
b. 2.98E-23
c. 2.84E27
d. 3.35E22
1 mol 6.0221E23 molecules
⋅
= 3.35E22 molecules
290.81 g
mol
(0 points) What is your Chmy 141, College Chemistry I, section?
a. Sec. 1 (10 AM)
b. Sec. 2 (11 AM)
c. Sec. 3 (8 AM)
34. Extra Credit – 5 points
What is the empirical formula of a compound with the following percent composition by
mass; 32.79% Na, 13.02% Al, and 54.19% F?
a. NaAl2F4
b. Na2Al2F3
1mol
= 1.426 mol
23.0 g
1 mol
13.02g ⋅
= 0.4822 mol
27.0 g
1 mol
54.19 g ⋅
= 2.852 mol
19.0 g
Na 1.426 Al 0.4822 F2.852
c. Na3AlF6
d. Na5Al2F8
32.79 g ⋅
Fission - A
Na 3 AlF6
7
Useful Formulae and Constants °F = °C(9 /5) + 32.0
Avogadro’s Number 6.0221 x 1023 mol-1 ; 1 inch = 2.54 cm
1 m = 102cm
1 L = 1.0567 qt 1 lb = 453.6 g
1 pm = 10-12 m
12 in = 1 ft
1 mi = 1.609 km = 5280 ft volume = l ⋅ w ⋅ h
1 nm = 10-9 m
FW = formula weight
1.6605402E-27 kg amu-1
1 gal = 4 qt
Fission - A
8