Distillation: simple distillation | Starter Quiz | Oak National Academy

Which of the following processes describes when a substance in the liquid state turns into the gas state?

• melting

• boiling

• condensing

• evaporating

• freezing

Answer explanation

Evaporation and boiling both involve a substance in the liquid state being changed into the gas state (both are examples of vaporisation).

Which property of matter does not change when a substance changes state?

• shape

• volume

• mass

• state

Answer explanation

The mass of a substance remains constant during changes of state.

What laboratory equipment is used to measure the volume of liquids accurately?

• Bunsen burner

• beaker

• measuring cylinder

• balance

• conical flask

Answer explanation

A measuring cylinder is designed to accurately measure the volume of liquids.

True or false? The boiling point of a liquid is the temperature at which it becomes a gas.

• true

• false

Answer explanation

The boiling point is the temperature at which a liquid changes state to become a gas.

Sort the following substances from the one which will boil first to the substance which will boil last when heated.

• water boils at 100°C

• aluminium boils at 2519°C

• sodium chloride boils at 1465°C

• ethanol boils at 78°C

Answer explanation

Substances have different boiling points. When heated, the substance with the lowest boiling point will boil first.

Match up the processes below to their descriptions.

• evaporation

• where a liquid turns into a gas at a specific temperature

• boiling

• where a gas is changed into a liquid

• condensation

• where a liquid turns into a gas at the substance's surface

Answer explanation

Evaporation occurs at any temperature, typically at the surface of the liquid, while boiling occurs throughout the liquid at a specific temperature. Condensation is the process of a gas turning into a liquid.