Chapter 14:
Gases
Practice Test
1.
If the pressure exerted by a gas at 100°C in a volume of 0.044 L is 3.81 atm, how many moles of gas are present?
a.
100 mol
b.
1.0 mol
c.
1.8 × 10
2
mol
d.
5.5 × 10
-3
mol
Hint
2.
A gas occupies a volume of 1.0 L at 25°C. What volume will the gas occupy at 100°C?
a.
4.0 L
b.
1.3 L
c.
0.80 L
d.
1.0 L
Hint
3.
A 10.0-L vessel contains gas A at a pressure of 300.0 torr. A 3.00-L vessel contains gas B at a pressure of 400.0 torr. Gas A is forced into the second vessel. Calculate the resulting pressure in torr. Assume the temperature remains constant.
a.
1800 torr
b.
1400 torr
c.
2000 torr
d.
1000 torr
Hint
4.
According to the following equation, how many liters of carbon dioxide will be produced when 10 L of methane are combusted?
a.
1.0 L
b.
2.0 L
c.
10 L
d.
0.1 L
Hint
5.
What is the volume of 2.0 moles of a gas at STP?
a.
22.4 L
b.
0.0446 L
c.
44.8 L
d.
0.0223 L
Hint
6.
A gaseous compound is 30.6% nitrogen and 69.4% oxygen by mass. A 5.25-g sample of the gas occupies a volume of 1.00 L and exerts a pressure of 1.26 atm at –4.0°C. What is the molecular formula for the gas?
a.
N
2
O
2
b.
NO
c.
N
3
O
6
d.
NO
2
Hint
7.
If 1.00 L of a gas is 4.40 times as heavy as 1.00 L of O
2
at the same temperature and pressure, then what is the molar mass of the unknown gas?
a.
67.0 g/mol
b.
141 g/mol
c.
70.4 g/mol
d.
88.0 g/mol
Hint
8.
A sample of helium occupies 2.20 L at 1.0 atm. What is the volume at 1.5 atm?
a.
2.20 L
b.
1.0 L
c.
0.68 L
d.
1.5 L
Hint
9.
What will happen to a real gas when the temperature is lowered and the pressure is raised?
a.
The gas eventually condenses to become a liquid.
b.
The number of gas particles doubles.
c.
The gas does not change.
d.
The gas expands.
Hint
10.
What is the molar mass of a gas if 0.104 g of the gas occupies 48.7 mL at STP?
a.
40.0 g/mol
b.
28.2 g/mol
c.
34.5 g/mol
d.
47.9 g/mol
Hint
11.
How can the molar volume of a gas be defined?
a.
the volume that one gram occupies at 100
C and 1 atm pressure
b.
the volume that one gram occupies at STP
c.
the volume that one mole occupies at STP
d.
the volume that one mole occupies at 100
C and 1 atm pressure
Hint
12.
What is the name given to the conditions in which the temperature is the freezing point of water and the pressure is one atmosphere?
a.
standard temperature and pressure
b.
combined gas law
c.
ideal gas
d.
standard state
Hint
13.
A gas occupies a volume of 1.0 L at 1.0 atm pressure. What is the pressure when the gas expands to fill 2.0 L?
a.
2.0 atm
b.
0.50 atm
c.
10 atm
d.
1.0 atm
Hint
14.
How can gases be defined?
a.
A physical state of matter that does not have a fixed shape but has a fixed volume.
b.
A physical state of matter that has a fixed volume and a fixed shape.
c.
A physical state of matter that does not have a fixed shape or a fixed volume.
d.
A chemical state of matter.
Hint
15.
When will the molecules of all samples of ideal gases have the same average kinetic energies?
a.
at constant volume
b.
at constant temperature
c.
at constant amount
d.
at constant pressure
Hint
16.
How many grams of ammonia (NH
3
) are present in a sample that occupies 2.0 L at a pressure at 2.0 atm and 25°C?
a.
6.3 grams
b.
2.7 grams
c.
0.16 grams
d.
0.36 grams
Hint
17.
Particles of matter that are in constant, random motion and that have a size that is much smaller than the distance between them are _____________.
a.
solids
b.
liquids
c.
gases
d.
solutions
Hint
18.
Which of the following states that equal volumes of gases at the same temperature and pressure contain the same number of particles?
a.
Gay-Lussac’s law
b.
Avogadro’s principle
c.
Charles’s law
d.
Boyle’s law
Hint
19.
What relationship is demonstrated by the expansion of a gas-filled balloon when it is heated?
a.
Charles’s law
b.
Boyle’s law
c.
Gay-Lussac’s law
d.
Avogadro’s number
Hint
20.
A gas occupies 2.0 L at STP. What volume will the gas occupy if the pressure is increased to 2.0 atm, and the temperature is kept constant?
a.
2.0 L
b.
0.50 L
c.
4.0 L
d.
1.0 L
Hint
