the change of state from a solid to a liquid that happens at a fixed temperature for pure substances

the change of state from a liquid to a gas that happens at a fixed temperature for pure substances

changing from a solid to a liquid or liquid to gas (or the reverse)

A heating curve for water

Combined science

In the Nuclear physics unit, pupils will build on this knowledge to learn about subatomic particles, unstable nuclei, radioactive decay, ionising radiation and radioactive half-life.

In the Particle explanations of density and pressure unit, pupils learnt how the arrangement and movement of particles in solids, liquids and gases explain density, pressure, floating and convection.

Energy of moving particles

Physical activity and equipment requiring safe use

Match the following key words to their definition.

Match the following states of matter to the description of particle behaviour.

The particles gain mass, so take up more space.

The individual particles grow larger, so take up more space.

The average particle speed increases, so they occupy a larger volume.

The empty space between particles decreases.

New particles are made by the extra energy, so the solid takes up more space.

Why do most solids expand when their temperature increases?

the change of state happens at an exact temperature

the change of state can happen over a range of temperatures

Which of the following statements describes what happens when a pure substance boils and changes from a liquid to a gas?

Which of the following statements describe what happens when a pure substance freezes and changes from a liquid to a solid?

The melting point of X and Y are the same.

The melting point of X must be higher than that of Y.

The melting point of Y must be higher than that of X.

Substance X will increase in temperature more quickly than substance Y.

Substance X will increase in temperature more slowly than substance Y.

Equal masses of samples of different substances, X and Y, are heated at the same rate. Substance X has a higher specific heat capacity than substance Y. Which of the following statements is correct?

Which of the following processes happen when two everyday objects at different temperatures are placed in contact with each other?

Which of the following pieces of equipment should be used to measure the change in temperature of a substance?

Which of the following pieces of equipment should be used to accurately measure the volume of a sample of a liquid?

After heating, allow the apparatus to cool before handling it.

Leave the room to avoid the possibility of burns.

Which of the following are precautions that should be used when heating a beaker of water using a Bunsen burner?

energy required  = mass + specific heat capacity + temperature change

energy required  = mass × specific heat capacity × temperature change

energy required  = mass × specific heat capacity ÷ temperature change

energy required  = mass × specific heat capacity

energy required  = mass + specific heat capacity × temperature change

Which of the following is the correct equation to calculate the energy required to increase the temperature of a material?

The particles in the water are different to the particle in the ice.

The arrangement of the particles changes as the ice melts.

On average, the particles move faster as the temperature increases.

A block of pure ice is heated in a beaker until it has all melted. Which of the following statements are correct?

Content guidance

Risk assessment required - equipment

Adult supervision required

This lesson will be removed by end of Summer Term 2025.

A heating curve for water

Lesson outcome

Content guidance

This lesson will be removed by end of Summer Term 2025.