Dissolving, Mixtures and Changes of State - Lesson Plan

In this comprehensive science lesson plan, students in Year 5 will delve into the fascinating world of reversible changes, focusing on dissolving, mixtures, and changes of state. The lesson aligns with the National Curriculum, building on knowledge from previous years, where students identified materials and observed changes in state. Through a series of activities, they will explore how dissolving and mixing are reversible physical changes, and learn to identify the components of a solution—solute and solvent. The lesson also addresses common misconceptions, such as the idea that solutes are destroyed when dissolved, and clarifies that mixtures like air and orange juice are not pure substances but combinations of different elements and compounds.

Students will engage in hands-on experiments to make solutions, observe the solubility of different solids, and investigate the effect of temperature on solubility. They'll use clear plastic cups, measuring cylinders, and various solutes like salt, sugar, bicarbonate of soda, and citric acid to conduct their experiments. The lesson also includes a teacher demonstration on the reversibility of changes in state, using ice, water, and steam to show the transition between solid, liquid, and gas. Additionally, an activity with chocolate will help students understand that melting and freezing are reversible processes. The lesson concludes with a plenary where pupils assess their understanding of the concepts covered. Safety precautions are emphasized throughout, ensuring a secure learning environment for all experiments.