KS3 ~ Year 7 ~ Diffusion

This lesson is designed for the Activate KS3 Science Course, specifically Year 7 C1.1 ’Particles & their Behaviour’

For more lessons designed for KS3 and KS4 please visit my shop at: https://www.tes.com/teaching-resources/shop/SWiftScience.

This lesson begins with an introduction to the process of diffusion, spraying perfume particles in the air is used as an example. Students are shown, by way of a particle diagram, how particles spread from an area of higher concentration to a lower concentration. Students are now asked to ‘copy and complete’ a paragraph to define the process of diffusion, this task can be assessed using the answers provided.

Next, students will need to sketch diagrams demonstrating the various stages of diffusion, and will need to match the correct statements to the correct diagrams. This work can be then be self or peer assessed using the mark scheme provided.

The next part of the lesson looks at factors that affect diffusion, students are firstly asked to ‘Think > Pair > Share’ their ideas on the factors which might affect the rate of diffusion. After students have fed back into class discussion, the answers are revealed for students to note down in their books. They will then look more closely at the effect of temperature on the rate of diffusion by watching a video and then summarising what they have learned by completing a fill-in-the-blank task.

Two other factors which affect the rate of diffusion are particle size and state of matter. Students are shown a diagram and given an explanation for how particle size affects the rate of diffusion - the heavier the particle the slower it is to diffuse. Students are then asked to consider whether particles will diffuse more quickly in the gaseous state, compared to liquid or solid state. Their answers can be discussed in pairs before feeding back to the class, the answers can then be revealed using the mark scheme provided.

Lastly, students will need to explain, in terms of particles, why a solid is unable to undergo diffusion whereas a gas and a liquid are able to.

The plenary activity requires students to write down 3 facts and 3 key words from the lesson and pose one question to test their peers on what they have learned this lesson.

All resources are included at the end of the presentation. Thanks for looking, if you have any questions please let me know in the comments section and any feedback would be appreciated :)