Substances in the gas state can be compressed to take up less space.

All substances are made of tiny particles, these move differently depending on the state of matter of the substance.

In a gas state the particles have a random movement, they move in all directions.

Compress means that something can be made to take up less space than before. Substances in the gas state can be compressed.

Particle model of substances in the gas state

Science

In the Solutions unit, pupils will build on their understanding of the states of matter to learn about mixtures, solutions, and dissolving in terms of the particle model.

In Y4 of primary science, pupils learnt about ‘solids, liquids and gases’ and changes of state.

This unit covers the properties of solids, liquids, and gases using the particle model, including gas pressure. It explains changes of state in terms of the particle model while developing skills in using appropriate techniques, apparatus, and materials in lab work.

Solid, liquid, gas states and changes of state

Physical activity and equipment requiring safe use

Which state of matter allows particles to fill the whole of a container and be compressed?

What is the primary characteristic of the movement of particles in the gas state?

Order the following states of matter based on the strength of the forces of attraction between particles. Start with the state of matter which has the strongest forces of attraction between particles.

Volume reduces due to increased pressure bringing particles closer together.

Reducing the size whilst maintaining the quality.

Assessing a material's resistance to distortion under force.

Which is the correct definition of compression, when referring to substances in the gas state being compressed? 

Because their particles move in fixed positions

Because their particles are larger than liquids and solids

Because their particles move freely and spread out

Why can substances in the gas state flow and fill the shape of their container?

Between particles in the gas state there is {{}}.

When a substance is compressed, it is said to take up {{}} space than before.

What happens to the particles in a substance when it changes from the liquid to solid state?

When a substance changes from solid state to liquid state, it is said to have {{}}.

In which state of matter are particles closest together?

True or False? When a substance changes state, its mass will change (either increase/decrease)?

Content guidance

Risk assessment required - equipment

Adult supervision required

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

Particle model of substances in the gas state

Lesson outcome

Content guidance

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