Teaching conservation of mass at 14–16

The law of conservation of mass is central to our understanding of reactions and therefore chemistry in general. Students need to have a good understanding of this topic, however they can struggle to connect the abstract with the observable reality of the law. Learners often have questions from their everyday lives that you can link to this topic and use to activate their thinking and prior knowledge. Use these teaching suggestions and classroom activities to build on learners’ prior knowledge and dispel misconceptions, then check for understanding with the help of Johnstone’s triangle.