This is a lesson which meets specification points within the WJEC GCSE ‘The Sciences’ Double Award (2026) spec, specifically from Unit 2.3 - Rate of reaction (Chemistry).

The lesson starts with an overview of the key vocabulary which students will be learning and using this lesson. Students can stick their key word lists into their books before the lesson begins.

Students are firstly introduced to collision theory, outlining the conditions which need to be in place in order for a chemical reaction to occur. Next students are asked to ‘Think, Pair, Share’ factors which they think may affect the rate of a reaction, once students have had chance to discuss this they are introduced to the four main factors which they study within this topic.

Firstly, the lesson will focus on surface area, this factor is explained using apple slices turning brown as an example, students are then introduced to the relationship between surface area to volume ratio and the rate of reaction. Students will then need to complete a worksheet of surface area to volume ration calculations, this can then be self-assessed using the mark scheme available.

Students will now work through a set of levelled questions looking at data on the effect of surface area on the rate of reaction, this work can be self-assessed using the mark scheme provided in the PowerPoint presentation.

The next part of the lesson will focus on the effect of temperature on the rate of reaction, students will firstly need to answer questions whilst watching a video, this work can then be self-assessed using the mark scheme. Next, students will carry out an investigation into the effect of temperature on the rate of reaction between sodium thiosulphate and hydrochloric acid. Students will need to collect data and use this to work out the rate of reaction at different temperatures, a worksheet is provided for this task.

The last task is for pupils to complete a ‘Quick Check’ set of questions in order to assess what they have learned this lesson, students can then either peer-assess or self-assess their work using the mark scheme provided.

The plenary task is for pupils to write a twitter message about what they have learned this lesson, included a hashtag of key words.

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 :)