This lesson is designed for the NEW AQA Trilogy Chemistry GCSE, particularly the ‘Rates of Reaction’ SoW.
 
The lesson begins with a ‘Think > Pair > Share’ task whereby students need to consider what it means for a reaction to be in ‘equilibrium’ . After a class discussion, the definition of a reversible reaction (in a closed system) to be at equilibrium is revealed to the class, which they can note down in their books.
 
This is further explained using a set of diagrams to depict what happens to the concentration of reactants and products during the course of a reversible reaction. Students can sketch a graph into their book to show how the equilibrium of a reversible reaction is reached.
 
The next task focuses on ‘Le Chatelier’s Principle’, students are firstly introduced to the idea that the equilibrium of a reversible reaction can be altered by changing the conditions of that reaction, i.e. an increase in temperature. Students will then be shown a set of demonstrations (video links included) for each they will need to note down their observations, identify the conditions which are changing and match the correct reaction to the correct word equation. Pupils will complete a worksheet for this task, which will be assessed using the mark scheme provided.
 
For the next part of the lesson, students will watch a video on the effect of pressure on equilibrium and answer a set of questions. These questions can be self-assessed using the answers provided on the PowerPoint.
 
Students will now ‘Think > Pair > Share’ the effect of an increase in temperature on the equilibrium of a reversible reaction, the answer is then revealed to pupils using an example. Pupils will now complete a ‘Quick Check’ task where they will be required to answer a set of questions about the reversible reactions and the effect of altering conditions on dynamic equilibrium. Pupils can self-assess their work using the answers provided on the PowerPoint.