Lesson 7 — Observing Chemical Change (Demonstration Task)

Chemical sciences, observation task. The teacher demonstrates a sequence of changes (melting butter, toasting bread, popping popcorn, melting/refreezing ice, burning paper) and students classify each as reversible or irreversible in a results grid, noting any new substance and the safety risk. Aligns to the 'Observing chemical change' sample assessment. Includes a slide deck, the Observing Chemical Change Results Grid worksheet, and the teacher demonstration-sequence card resource.