Gas Behavior Practice Questions

1. 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 get closer together

Molecules collide with the inside of the balloon with greater force

Molecules get farther apart

Pressure inside the balloon goes up

Molecules move faster

Question 1 of 15

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

(Check all that apply)

Molecules are getting closer together

Higher pressure / more collisions between molecules

Molecules are getting farther apart

Air is getting warmer / molecules are moving faster

Air is getting colder / molecules are moving slower

Water molecules are going from liquid to gas

Lower pressure / less collisions between molecules

Water molecules are going from gas to liquid

Question 2 of 15

3. 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 higher

The pressure will be 3 times lower

The volume will be 3 times lower

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

20 kPa

180 kPa

80 kPa

Question 4 of 15

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

13.5 °C

327 °C

150 K

54 °C

Question 5 of 15

6. 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 air pressure is decreasing

The air molecules are moving slower

The air molecules are getting farther apart

The air molecules collide with the marshmallows less frequently

The total number of air molecules is decreasing

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

Question 6 of 15

Which statements about the thermosphere are true?

(check all that apply)

We live in this layer

This is the coldest layer of the atmosphere

The temperature in this layer increases as you go up

The air in this layer is extremely thin

The ozone layer is located in this layer

This layer is exposed to direct sunlight

Question 7 of 15

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

(Check each true statement)

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

$P_1 V_1 = P_2 V_2$

The volume gets 7 times larger

The volume gets 7 times smaller

Pressure and volume are directly related

Pressure and volume are inversely related

Question 8 of 15

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

(check all that apply)

Air flows from high pressure to low pressure

Molecules in your lungs get farther apart

Number of air molecules in your lungs increases

Pressure in your lungs increases

Volume of air inside lungs decreases

Question 9 of 15

10.

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

Not enough information provided in problem.

0.25 atm

4 atm

Question 10 of 15

11. 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?

9 L

4 L

1 L

36 L

Question 11 of 15

12. Which atmospheric layer do we live in?

Stratosphere

Mesosphere

Thermosphere

Exosphere

Troposphere

Question 12 of 15

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

(check all that apply)

Molecules are colliding with the container less often

Molecules are getting farther apart

Pressure increases

Molecules are getting closer together

Pressure decreases

Molecules are colliding with the container more often

Question 13 of 15

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

Thermosphere

Mesosphere

Stratosphere

Exosphere

Troposphere

Question 14 of 15

15. Which of these temperatures is the coldest?

220 K

32 °F

-20 °C

1,000,000 °F

Question 15 of 15