Unit 10 Study Guide
11.
You are holding two helium balloons, a large and
a small balloon. How do the pressures of the helium
compare?
A)
The pressure in the large balloon is
greater than the pressure in the small balloon.
This is best explained by the fact that there must
be more moles of gas in the large balloon, thus
greater pressure.
B)
The pressure in the small balloon is
4.
Perform the following conversion of pressure
greater
than the pressure in the large balloon.
units:
This
is
best
explained by the fact that as the
1.198 atm = ____________ torr
volume
of
a
container decreases, the pressure of
A)
910.5
the
gas
increases.
B)
634.4
C)
The pressure in the large balloon is
C)
1.576  10–3
greater than the pressure in the small balloon.
D)
17.61
The fact that there is a greater pressure in the
E)
1.198
balloon explains why the volume is larger; as the
Ans: A
particles push more on the inside, the volume
increases.
6.
Perform the following conversion of pressure
D)
The pressures are essentially the same and
units:
less
than
atmospheric pressure.
9
8.6  10 Pa = ____________ atm
E)
The pressures are essentially the same and
4
A)
1.1  10
equal to atmospheric pressure.
B)
1.7  105
Ans: E
5
C)
5.9  10
D)
1.3  1011
13.
A certain balloon will pop if it expands to a
E)
8.5  104
volume greater than 16.0 L. The balloon is currently
Ans: E
filled with air at a volume of 8.0 L. You heat the balloon
such that the temperature measured in degrees Celsius
8.
Perform the following conversion of pressure
doubles. Which of the following best describes what
units:
happens?
0.755 atm = ____________ torr
A)
The balloon will expand to a volume
A)
1007
greater than 16.0 L and pop.
B)
76.5
B)
The balloon will expand to a volume less
C)
11.10
than 16.0 L and not pop.
D)
574
C)
The balloon will expand to a volume of
E)
599
16.0 L and pop.
Ans: D
D)
The balloon will expand to a volume of
16.0 L and not pop.
10.
Consider a gas at 1.00 atm in a 5.00-L container
E)
The volume of the balloon will remain the
at 20.oC. What pressure does the gas exert when
same
but
the pressure will increase.
transferred to a volume of 3.53 L at 43 oC?
Ans: B
A)
3.05 atm
B)
1.31 atm
15.
When analyzing ideal gases, the temperature
C)
0.371 atm
must be measured on the Kelvin scale
D)
1.53 atm
A)
because otherwise you could calculate a
E)
0.761 atm
negative volume.
Ans: D
B)
so that you are using an absolute scale.
C)
to directly measure the average kinetic
energy of the gas particles.
D)
Both a and b are correct.
E)
a, b, and c are correct.
Ans: E
2.
Convert 9.88  102 torr to psi.
A)
1.30 psi
B)
19.1 psi
C)
1.45  104 psi
D)
5.11  104 psi
E)
1.43  102 psi
Ans: B
18.
You have a sample of argon gas at a certain
pressure, volume, and temperature. You double the
volume, double the number of moles of argon, and double
the Kelvin temperature. How does the final pressure (Pf)
compare to the original pressure (Po)? Pf =
A)
(1/8)Po
B)
(1/2)Po
C)
2Po
D)
4Po
E)
8P2
Ans: C
20.
What is the volume of a helium balloon that
contains 3.13 mol helium at 27oC and 1.10 atm?
A)
6.30 L
B)
63.7 L
C)
77.1 L
D)
70.0 L
E)
6.93 L
Ans: D
21.
A sample of a gas in a container fitted with a
piston has a temperature above 0°C. The Celsius
temperature is doubled. What is true about the ratio of
final volume to initial volume for the gas?
A)
It is 1:1.
B)
It is 2:1.
C)
It is 1:2.
D)
It is greater than 2:1.
E)
It is less than 2:1.
Ans: E
22.
You have a partially filled party balloon with
2.00 g of helium gas. You then add 3.00 g of hydrogen
gas to the balloon. Assuming constant temperature and
pressure, how many times bigger is the party balloon –
comparing before and after the hydrogen gas has been
added. Choose the best formula to use to solve this
problem. (V = volume of the gas, n = moles of the gas, m
= mass of the gas, P = pressure of the gas.)
A)
B)
C)
D)
E)
V2 n2

V1 n1
V2 m2

V1 m1
P2 n2

P1 n1
V2 T2

V1 T1
PV
1 1  PV
2 2
Ans: A
25.
A sample of helium gas occupies 11.6 L at 23oC
and 0.956 atm. What volume will it occupy at 40. oC and
0.956 atm?
A)
20.2 L
B)
0.0815 L
C)
11.0 L
D)
12.3 L
E)
none of these
Ans: D
28.
If temperature and pressure are held constant, the
volume and number of moles of a gas are
A)
independent of each other
B)
directly proportional
C)
inversely proportional
D)
equal
E)
not enough information given
Ans: B
31.
2.37 mol of CO2 at STP will occupy
A)
58.0 L
B)
53.1 L
C)
6.99  10–2 L
D)
26.5 L
E)
53.1 g
Ans: B
34.
You are holding two balloons of the same
volume. One balloon contains 1.60 g helium. The other
balloon contains neon. What is the mass of neon in the
balloon?
A)
0.400 g
B)
1.60 g
C)
50.5 g
D)
8.07 g
E)
20.0 g
Ans: D
35.
You fill a balloon with 10.0 g of N2 gas. You
wish to add 10.0 g of another gas to make the balloon
more than twice as large as it is with only the N2 (that is,
more than twice the original volume). Which gas should
you add (assume constant temperature)?
A)
O2
B)
CO2
C)
CO
D)
He
E)
You cannot make the balloon more than
twice as large with 10.0 g of any gas.
Ans: D
37.
Suppose a balloon has a maximum volume of
7.00 L. Also suppose each time you blow into a balloon,
you expel 0.045 mol of air. How many times can you
blow into the balloon before the balloon pops? Assume
atmospheric conditions of 1.0 atm and 22°C and that your
breath is at room temperature.
Ans: We can blow into the balloon 6 times. It
will pop during the seventh time.
47.
A gas occupies 20.1 L at 2.00 atm pressure and
27oC. Calculate its volume if the pressure remains at 2.0
atm but the temperature is raised to 54oC.
A)
18.4 L
B)
40.2 L
C)
0.0456 L
D)
21.9 L
E)
14.7 L
Ans: D
39.
You are holding four balloons each containing
10.0 g of a different gas. The balloon containing which
gas is the largest?
A)
H2
B)
He
C)
Ne
D)
O2
E)
All have the same volume.
Ans: A
49.
A gas occupies 25.3 L at 2.00 atm pressure and
27oC. How many moles of gas are present in the sample?
A)
22.8 mol
B)
1.03 mol
C)
2.06 mol
D)
3.56 mol
E)
4.46 mol
Ans: C
51.
41.
A specified quantity of an unknown gas has the
volume of 19.8 mL at 22oC and 659 torr. Calculate the
volume at STP.
A)
1.28 mL
B)
18.6 mL
C)
15.9 mL
D)
21.1 mL
E)
none of these
Ans: C
43.
A 251-mL sample of a gas at STP is heated to
45oC. The final pressure is 1.47 atm. Calculate the volume
of this gas under the new conditions.
A)
28.1 mL
B)
147 mL
C)
6822 mL
D)
199 mL
E)
133 mL
Ans: D
45.
A 11.1-L sample of gas at STP is heated to 55oC
at 605 torr. What is the new volume?
A)
16.8 L
B)
2.81 L
C)
11.6 L
D)
10.6 L
E)
11.2 L
Ans: A
46.
A gas occupies 20.3 L at 2.00 atm pressure and
27oC. Calculate its volume if the pressure is decreased to
1.00 atm at constant temperature.
A)
10.2 L
B)
40.6 L
C)
60.9 L
D)
13.6 L
E)
81.2 L
Ans: B
What volume will 46.8 g of N2 occupy at STP?
A)
40.9 L
B)
4.93  10–2 L
C)
37.4 L
D)
3.43 L
E)
none of these
Ans: C
53.
The volume of a sample of gas is 637.6 mL at
STP. What volume will the sample occupy at 0.0oC and
950.0 torr?
A)
797.0 mL
B)
510.1 mL
C)
467.3 mL
D)
622.1 mL
E)
none of these
Ans: B
55.
What volume is occupied by 36.3 g of methane,
CH4, at 27oC and 1.59 atm?
A)
55.7 L
B)
35.0 L
C)
3.15 L
D)
50.6 L
E)
not enough data to calculate
Ans: B
58.
Zinc metal is added to hydrochloric acid to
generate hydrogen gas and is collected over a liquid
whose vapor pressure is the same as that of pure water at
20.0oC (18 torr). The volume of the mixture is 1.7 L, and
its total pressure is 0.973 atm. Determine the number of
moles of hydrogen gas present in the sample.
A)
0.98 mol
B)
0.138 mol
C)
0.27 mol
D)
0.067 mol
E)
0.039 mol
Ans: D
60.
A gas is collected over water at a certain
temperature. The total pressure is 756 torr. The vapor
pressure of water at this temperature is 17 torr. The partial
pressure of the gas collected is
A)
756 torr
B)
17 torr
C)
773 torr
D)
739 torr
E)
731 torr
Ans: D
79.
The largest a party balloon can get before
bursting is 9.16 L at 25oC and 1.00 atm. Supposing you
fill the balloon only with oxygen gas, how many grams of
oxygen can be added to the balloon before it pops?
Assume you have not yet added any gas to the balloon at
all (so essentially the balloon is flat).
A)
12.0 g O2
B)
0.375 g O2
C)
4.47 g O2
D)
143 g O2
E)
2.67 g O2
Ans: A
80.
A sample of oxygen gas (O2) has a volume of
7.89 L at a temperature of 19oC and a pressure of 1.38
atm. Calculate the moles of O2 molecules present in this
gas sample.
A)
6.98 mol
B)
0.454 mol
C)
0.909 mol
D)
0.227 mol
E)
none of these
Ans: B
81.
A flexible weather balloon contains helium gas at
a volume of 855 L. Initially, the balloon is at sea level,
where the temperature is 25oC and the barometric pressure
is 0.947 atm. The balloon then rises to an altitude of 5500
ft, where the pressure is 0.756 atm and the temperature is
15oC. What is the change in the volume of the balloon as
it ascends from sea level to 5500 ft?
A)
180. L
B)
1035. L
C)
216. L
D)
639. L
E)
216. L
Ans: A
83.
A hydrogen balloon is at 25oC, 1.00 atm and has
a volume of 1.00 L. How many grams of argon gas must
be added to the hydrogen balloon to achieve a volume of
3.71 L at constant temperature and pressure?
A)
6.06 g
B)
7.69 g
C)
90.7 g
D)
4.43 g
E)
none of these
Ans: D