Question 1

In kinetic theory, a gas is modeled as being made up of a large number of molecules which bounce from the walls of the container.

Accepted Answer

This statement is true according to the kinetic theory of gases.

Question 2

When both the pressure and the absolute temperature of an ideal gas are increased each by a factor of two, the volume occupied by the gas will
A) increase by a factor of four.
B) increase by a factor of two.
C) not change.
D) decrease by a factor of two.
E) decrease by a factor of four.

Accepted Answer

According to the ideal gas law, PV = nRT, the volume is directly proportional to the absolute temperature (T) and inversely proportional to the pressure (P). When both P and T are doubled while n and R remain constant, PV = nRT holds true. Therefore, V (volume) must also remain constant, leading to choice C.

Question 3

The internal energy of an ideal gas does not depend on the pressure.

Accepted Answer

The internal energy of an ideal gas depends only on the temperature, and not on the pressure or volume. This is known as the ideal gas law or the first law of thermodynamics.

Question 4

When comparing two gases at the same temperature, the gas with a higher molecular weight has more internal energy per mole.

Accepted Answer

The internal energy of a gas depends on its temperature and does not depend on its molecular weight. Therefore, two gases at the same temperature will have the same internal energy per mole regardless of their molecular weight.

Question 5

The pressure in a gas is the result of the momentum transfer that occurs when the molecules bounce from the walls of the container.

Accepted Answer

This is a basic principle of the Kinetic Theory of Gases, which explains the behavior of gases based on the motion of their molecules. The pressure of a gas is related to the frequency and momentum of these molecular collisions with the container walls.

Question 6

According to kinetic theory, the temperature of a gas is determined by the average kinetic energy of its molecules. What would happen if the gas were in a container that was moving with a high velocity?

Accepted Answer

The answer of According to kinetic theory, the temperature of...

Question 7

You have had something simmering in a covered pot on the stove and then turn off the heat. Some time later you return to the pot and find that you have trouble lifting the lid. Why?

Accepted Answer

The answer of You have had something simmering in a...

Question 8

Explain why, when someone across the room pierces a can of coffee with a can opener, you hear the sound of the can being pierced before you smell the aroma of the coffee.

Accepted Answer

The answer of Explain why, when someone across the room...

Question 9

On a cold winter day, you turn up the thermostat in your house. Assume that your house is well sealed and that no air enters or leaves the house. When the air temperature in your house rises a short while later, what statement is correct regarding the air pressure?
A) The air pressure is higher at the higher temperature.
B) The air pressure is lower at the higher temperature.
C) The air pressure does not change at the higher temperature.
D) The air pressure increases at first but then decreases again as the temperature approaches its higher value.
E) The air pressure decreases at first but then increases again as the temperature approaches its lower value.

Accepted Answer

When the temperature of a gas increases in a sealed container, the pressure also increases due to the direct relationship between temperature and pressure in the ideal gas law (assuming volume and amount of gas are constant).

Question 10

State Boyle's law.

Accepted Answer

The answer of State Boyle's law....

Question 11

In the deep ocean trenches, there are hydrothermal vents, which discharge very hot water. In one such vent, the temperature of the water is 300°C. Why does this water not boil?

Accepted Answer

The answer of In the deep ocean trenches, there are...

Question 12

When you are standing by an air conditioning vent in an indoor swimming pool area, you feel a lot cooler if you are wet than if you are dry. Why?

Accepted Answer

The answer of When you are standing by an air...

Question 13

State Charles's law.

Accepted Answer

The answer of State Charles's law....

Question 14

On a hot summer day, you turn the thermostat in your house way down. Assume that your house is well sealed and that no air enters or leaves the house. When the air temperature in your house falls a short while later, what statement is correct regarding the air pressure?
A) The air pressure is higher at the lower temperature.
B) The air pressure is lower at the lower temperature.
C) The air pressure does not change at the lower temperature.
D) The air pressure increases at first but then decreases again as the temperature approaches its higher value.
E) The air pressure decreases at first but then increases again as the temperature approaches its lower value.

Accepted Answer

When the air temperature in your house falls, the air molecules lose kinetic energy and move slower, resulting in a decrease in air pressure. This happens because the air molecules are not colliding with the walls of the house with as much force as they were when they had higher kinetic energy at the higher temperature. Therefore, the correct statement is that the air pressure is lower at the lower temperature.

Question 15

In tropical areas of the world where refrigeration is not readily available, people store water in unglazed clay pots. This makes the water stay at a cool temperature, much cooler than the ambient temperature. How is that possible?

Accepted Answer

The answer of In tropical areas of the world where...

Question 16

Ice melts if enough pressure is applied to it.

Accepted Answer

This is true. When pressure is applied to ice, it melts into liquid water because the pressure breaks the bonds between the ice molecules. This is the same principle that allows ice skaters to glide on the surface of ice - they apply pressure to the ice, causing it to melt briefly and reduce friction.

Question 17

When comparing two gases at the same temperature, the molecules of the gas with the smaller molecular weight have the higher rms speed.

Accepted Answer

According to the kinetic theory of gases, the rms speed of gas molecules is directly proportional to the square root of their temperature and inversely proportional to the square root of their molecular weight. Therefore, for two gases at the same temperature, the gas with the smaller molecular weight will have higher rms speed.

Question 18

What is the Maxwell distribution?

Accepted Answer

The answer of What is the Maxwell distribution?...

Question 19

When a spray can is being used, it feels cooler than when it was first picked up. Why?

Accepted Answer

The answer of When a spray can is being used,...

Question 20

The internal energy of an ideal gas does not depend on the volume.

Accepted Answer

The internal energy of an ideal gas depends only on the temperature and the number of particles in the gas. It is independent of the volume or pressure of the gas.

Quiz 17: Phases and Phase Changes