Particle pictures: solids, liquids and gases

Worksheets and lesson ideas to challenge students aged 11 to 16 to think hard about solids, liquids and gases (GCSE and Key Stage 3)

The particle model for solids, liquids and gases is a controversial topic in science education. Many teachers believe it introduces misconceptions that we spend time unpicking later. The concept must be approached with real caution so students are helped to make the link between the concrete substance and the abstract particle. The term particle should really be used to refer to an atom, molecule or ion. But how do we know particles are moving? The smoke cell video below is a great way to introduce particle movement in gases. 

Thinking about particle pictures and student misconceptionsDrawing particle pictures

Click here for an excellent review of misconceptions involving the particle model from the RSC.

KS3 worksheet for drawing particle pictures. Use peer assessment to mark particle pictures so students are able to “see” what the teacher is seeing. Drawing particle models in beakers can support the concepts of fixed shape and fixed volume, although it is also worth considering what is happening to particles outside the beaker. (PDF)

Tackling misconceptions about the particle model

KS3 worksheet to encourage students to think deeply about particle pictures and states of matter. The worksheet shows a particle picture of a gas within a solid glass jar. The jar is also drawn from particles. Students consider what exists between the gas particles and think about why some substances are gases at room temperature whilst others are solids. This task challenges students to think deeply about the particle model. The simple statement that gases have more energy than solids needs to be reconsidered – at the same temperature, particles of a gas, liquid and solid ALL have the same average kinetic energy. (PDF)

KS3 activity and worksheet on common particle model misconceptions. Students are presented with a number of questions that challenge common misconceptions about the particle model. This activity is best done in small groups. (PDF)

Pressure in gases and particle movement

KS3 activity to get students thinking about particle movement and gas pressure. Students think through a problem involving the movement of a single gas particle inside a container to help them understand pressure. This idea came from discussions with beginning science teachers. (PDF on pressure of gases and particle movement)

Latent heat and internal energy

Click here for resources on latent heat and internal energy stores.

  1. Particle pictures and the particle model
  2. Elements mixtures and compounds
  3. Separating techniques
  4. Solutions
  5. Density