Matter - Quiz No 2

Which statement about evaporation is correct?

• Evaporation causes the temperature of the remaining liquid to decrease.

• Evaporation does not occur from a cold liquid near its freezing point.

• Evaporation does not occur from a dense liquid, such as mercury.

• Evaporation occurs from all parts of a liquid.

A gas is stored in a sealed container of constant volume. The temperature of the gas increases. This causes the pressure of the gas to increase.

What happens to the gas molecules during this pressure increase?

• The average kinetic energy of the molecules increases.

• The average separation of the molecules decreases.

• The average separation of the molecules increases.

• The volume of each molecule increases.

A liquid is evaporating. The liquid is not boiling.

Which statement about the liquid is correct?

• Any molecule can escape, and from any part of the liquid.

• Any molecule can escape, but only from the liquid surface.

• Only molecules with enough energy can escape, and only from the liquid surface.

• Only molecules with enough energy can escape, but from any part of the liquid.

What causes the random, zig-zag movement (Brownian motion) of smoke particles suspended in air?

• air molecules colliding with smoke particles

• convection currents as the hot smoke rises

• smoke particles colliding with each other

• smoke particles reacting with oxygen molecules in the air

A sealed bottle of constant volume contains air. The air in the bottle is heated by the Sun.

What is the effect on the average speed of the air molecules in the bottle?

• It increases

• It decreases.

• It remains same

• Cannot be predicted.

A cup contains hot liquid. Some of the liquid evaporates.

What happens to the mass of the liquid in the cup?

• It Increases

• It decreases

• It remains same

• Depends on the temperature of the liquid.

Very small pollen grains are suspended in a beaker of water. A bright light shines from the side. Small, bright dots of light are seen through a microscope. The dots move in rapidly changing, random directions.

What are the bright dots?

• pollen grains being hit by other pollen grains.

• pollen grains being hit by water molecules.

• water molecules being hit by other water molecules.

• water molecules being hit by pollen grains.

A pool of water evaporates. As molecules escape, the temperature of the water left in the pool changes.

From where do the molecules escape and what is the effect on the temperature of the water in the pool?

• molecules escape from all parts of liquid.

  Temperature decreases.

• molecules escape from all parts of liquid.

  Temperature Increases.

• molecules escape from surface of the liquid.

  Temperature decreases.

• molecules escape from surface of the liquid.

  Temperature increases.

Two states of matter are described as follows.

In state 1, the molecules are very far apart. They move about very quickly at random in straight lines until they hit something.

In state 2, the molecules are quite closely packed together. They move about at random. They do not have fixed positions.

What is state 1 and what is state 2?

• 1: Gas

  2: Liquid

• 1: Liquid

  2: Gas

• 1: Solid

  2: Gas

• 1: Liquid

  2: Gas

The diagrams represent the molecules in two different states of matter.

The arrows show the motion of the molecules.

What is state 1 and state 2?

• 1: Solid

  2: Liquid

• 1: Gas

  2: Solid

• 1: Liquid

  2: Gas

• 1: Gas

  2: Liquid