Chemistry And Chemical Reactivity International Edition 8th Edition By Kotz – Test Bank

Chapter 11—Gases and Their Properties

MULTIPLE CHOICE

1. Convert 0.449 bar to mm Hg. (1 atm = 760 mm Hg = 101.3 kPa = 1.013 bar)
a. 337 mm Hg
b. 0.591 mm Hg
c. 5.89  10–4 mm Hg
d. 0.443 mm Hg
e. 0.455 mm Hg

ANS: A

2. Convert 618 mm Hg to kPa. (1 atm = 760 mm Hg = 101.3 kPa)
a. 0.0121 kPa
b. 1.23 kPa
c. 0.813 kPa
d. 82.4 kPa
e. 4.64  103 kPa

ANS: D

3. At 0.982 atm, the height of mercury in a barometer is 0.746 m. If the mercury were replaced with ethanol, what height of ethanol (in meters) would be supported at this pressure? The densities of Hg and ethanol are 13.5 g/cm3 and 0.789 g/cm3, respectively.
a. 0.0436 m
b. 0.946 m
c. 0.760 m
d. 12.8 m
e. 13.0 m

ANS: D

4. At constant temperature, 7.72 L of Cl2 at 458 mm Hg is compressed to 3.75 L. What is the final pressure of Cl2?
a. 0.485 mm Hg
b. 0.00106 mm Hg
c. 222 mm Hg
d. 943 mm Hg
e. 1820 mm Hg

ANS: D

5. If the volume of a confined gas is expanded to four times the original volume while its temperature remains constant, what change will be observed?
a. The pressure of the gas will decrease to 1/4 its original value.
b. The pressure of the gas will decrease to 1/2 its original value.
c. The pressure of the gas will remain unchanged.
d. The pressure of the gas will increase to twice its original value.
e. The pressure of the gas will increase to four times its original value.

ANS: A

6. The lid is tightly sealed on a rigid flask containing 2.25 L Ar at 22 C and 0.977 atm. If the flask is heated to 102 C, what is the pressure in the flask?
a. 2.86 atm
b. 1.27 atm
c. 4.53 atm
d. 0.769 atm
e. 1.73 atm

ANS: B

7. A tightly sealed 4.0-L flask contains 884 mm Hg of N2 at 94.0 C. The flask is cooled until the pressure is reduced 442 mm Hg. What is the temperature of the gas?
a. –47.0 C
b. 47.0 C
c. –89.5 C
d. 184 C
e. 188 C

ANS: C

8. A balloon is filled with He gas to a volume of 2.10 L at 35 C. The balloon is placed in liquid nitrogen until its temperature reaches –196 C. Assuming the pressure remains constant, what is the volume of the cooled balloon?
a. 0.375 L
b. 0.375 L
c. 0.525 L
d. 0.00909 L
e. 8.40 L

ANS: C

9. A 0.175-L flask contains Cl2 at 25 C and 475 mm Hg. What is the pressure of the Cl2 if the volume is increased to 0.800 L and the temperature increased to 55 C?
a. 239 mm Hg
b. 94.4 mm Hg
c. 114 mm Hg
d. 241 mm Hg
e. 228 mm Hg

ANS: C

10. You have a 30.0 L cylinder of helium at a pressure of 132 atm and a temperature of 19 C. The He is used to fill balloons to a volume of 1.80 L at 745 mm Hg and 27 C. How many balloons can be filled with He? Assume that the cylinder can provide He until its internal pressure reaches 1.00 atm (i.e., there are 131 atmospheres of usable He in the cylinder).
a. 1.90  102
b. 1.06  102
c. 4.13  103
d. 7.41  103
e. 2.29  103

ANS: E