Gas Behavior Practice Questions

1. Which of these temperatures is the coldest?

-20 °C

1,000,000 °F

32 °F

220 K

Question 1 of 15

2. If marshmallows are put in a vacuum chamber and the vacuum pump is turned on, the marshmallows will expand. During this process, what is happening with the air molecules outside the marshmallows (but inside the glass chamber)?

Vacuum Marshmallow Man

(Check all that apply)

The total number of air molecules is decreasing

The air pressure is decreasing

Each time a molecule hits the marshmallow, it collides with less force

The air molecules are moving slower

The air molecules collide with the marshmallows less frequently

The air molecules are getting farther apart

Question 2 of 15

3. When a balloon is heated, it expands. During this process, the pressure outside the balloon is constant at 1 atm. What is happening with the molecules to cause the balloon to get bigger?

(Check all that apply)

Molecules collide with the inside of the balloon with greater force

Molecules get closer together

Molecules get farther apart

Molecules move faster

Pressure inside the balloon goes up

Question 3 of 15

4. 3.0 L of a gas start out with a pressure reading of 120 kPa. When the volume is reduced to 2.0 L, what is the new pressure?

0.05 kPa

180 kPa

80 kPa

20 kPa

Question 4 of 15

5. A balloon has a starting volume of 6 L.

Then the balloon’s temperature is tripled, and its pressure is cut in half.

What is the new volume of the balloon?

1 L

9 L

4 L

36 L

Question 5 of 15

6. Which layer of our atmosphere is warmed up because it absorbs ultraviolet radiation?

Exosphere

Mesosphere

Stratosphere

Troposphere

Thermosphere

Question 6 of 15

Which statements about the thermosphere are true?

(check all that apply)

This layer is exposed to direct sunlight

The air in this layer is extremely thin

The ozone layer is located in this layer

We live in this layer

This is the coldest layer of the atmosphere

The temperature in this layer increases as you go up

Question 7 of 15

8. If a gas has a constant volume and its temperature triples, what happens to the pressure of the gas?

The volume will be 3 times higher

The pressure will be 3 times lower

The volume will be 3 times lower

The pressure will be 3 times higher

Question 8 of 15

9. A gas expands (volume increases). What is happening with its molecules to change its pressure?

(check all that apply)

Molecules are getting farther apart

Molecules are colliding with the container less often

Molecules are colliding with the container more often

Pressure increases

Pressure decreases

Molecules are getting closer together

Question 9 of 15

10. If the pressure of a gas sample gets 7 times higher, what happens to its volume?

(Check each true statement)

The volume gets 7 times smaller

The volume gets 7 times larger

$P_1 V_1 = P_2 V_2$

$\cfrac{P_1}{V_1} = \cfrac{P_2}{V_2}$

Pressure and volume are inversely related

Pressure and volume are directly related

Question 10 of 15

11. When you breathe in, what happens with the air molecules in your lungs?

(check all that apply)

Number of air molecules in your lungs increases

Air flows from high pressure to low pressure

Pressure in your lungs increases

Molecules in your lungs get farther apart

Volume of air inside lungs decreases

Question 11 of 15

12. Which atmospheric layer do we live in?

Exosphere

Thermosphere

Mesosphere

Troposphere

Stratosphere

Question 12 of 15

13.

A gas in a constant volume container has a starting temperature of 200 K, and it is at atmospheric pressure. If the temperature is increased to 800 K, what is the new pressure?

1 atm

4 atm

0.25 atm

Not enough information provided in problem.

Question 13 of 15

14. When moist air rises to form clouds, what is happening with the air molecules?

(Check all that apply)

Air is getting colder / molecules are moving slower

Water molecules are going from liquid to gas

Higher pressure / more collisions between molecules

Air is getting warmer / molecules are moving faster

Molecules are getting closer together

Water molecules are going from gas to liquid

Lower pressure / less collisions between molecules

Molecules are getting farther apart

Question 14 of 15

15. If a gas sample has a starting temperature of 27 °C and its volume is doubled, what would the new temperature be?

150 K

327 °C

54 °C

13.5 °C

Question 15 of 15