Lesson Idea | How to Purify Water

Description

This experiment demonstrates how contaminated water can be purified using a simple model of the water cycle. Learners place dirty water in a large container with an empty smaller container inside, then cover it with cling film weighted in the center. As the setup warms in sunlight, water evaporates, leaving contaminants behind, then condenses on the cling film and drips into the smaller container as cleaner water. The activity helps students understand evaporation, condensation, precipitation, reversible changes, and separation techniques while connecting these ideas to real-world situations such as producing drinking water in space or surviving on a desert island.