8 Kinetic Molecular of Matter 2022 J & N [EUT]

Which properties are correct for liquids?

• 1 and 2 only

• 2 and 3 only

• 1 and 3 only

• 1, 2 and 3

What happens to the volumes of liquid metal and of solid metal when heated at constant pressure?

(a)  

A particular state of matter consists of molecules that move freely in random directions at high speed. The average speed of the molecules is decreasing. Which state of matter is being described?

• a gas cooling

• a gas being heated

• a solid cooling

• a liquid being heated

Small pollen particles are suspended in water. When viewed with a microscope, the pollen particles can be seen to be moving about irregularly. What causes this movement?

• The pollen particles are being bombarded by the heavier particles of the water.

• The pollen particles are being bombarded by the lighter particles of the water.

• The temperature of the water is higher than that of the pollen particles.

• The temperature of the water is lower than that of the pollen particles.

The properties of two states of matter are listed.

State 1: The molecules move quickly and randomly. There is a large distance between the molecules.

State 2: The molecules vibrate about fixed positions. The molecules are closely packed together.

What are states 1 and 2?

• gas, liquid

• liquid, solid

• solid, liquid

• gas, solid

A gas in a container is cooled but the volume of the gas does not change. Which row describes the changes in the pressure of the gas and the average kinetic energy of the gas particles?

• decreases, decreases

• decreases, increases

• increases, decreases

• increases, increases

A sealed rigid container has a fixed volume. The container is filled with air.

The container is placed in a freezer cabinet and the temperature of the air in the container decreases. Which row correctly describes what happens to the air in the container?

(a)  

The conditions of a sample of gas change in two stages. Stage 1: Increase of temperature at constant volume Stage 2: Increase of volume with no further change of temperature Which row about the pressure after each stage is correct?

(a)  

Why do the gas particles exert a pressure on the wall?

• When the particles hit the wall, their momentum changes, which causes a force.

• When the particles hit the wall, their average kinetic energy increases.

• The particles expand when they hit the wall.

• The particles collide with each other.

A fixed mass of gas is trapped in a container. The temperature of the gas is increased but the volume of the gas is kept constant. How does this change affect the average kinetic energy of the molecules and the pressure on the walls of the container?

• average kinetic energy increases, pressure increases

• average kinetic energy stays the same, pressure increases

• average kinetic energy increases, pressure decreases

• average kinetic energy decreases, pressure increases