CBSE · Class 7 · Science · Chapter 5

Changes Around Us: Physical and Chemical

Distinguish physical and chemical changes while exploring rusting, burning, crystallisation, weathering and other transformations.

6 lessons 40 min
Start chapter

Lessons in this chapter

  1. 1Observing and Identifying Physical ChangesLearn how to observe everyday changes and decide whether the material itself has changed.
  2. 2How Chemical Changes Form New SubstancesUse simple investigations to recognise new substances and identify carbon dioxide with lime water.
  3. 3Rusting, Combustion, and the Fire TriangleExplore new substances formed by rusting and burning, and discover the three conditions a fire needs.
  4. 4More Ways to Classify ChangesSeparate the stages of a burning candle and compare changes by reversibility and usefulness.
  5. 5Weathering and ErosionFollow slow changes from cracking rocks to soil, transported sediments, and new rock.
  6. 6Chapter Summary and PracticeConnect the complete chapter through a recap table, worked reasoning, and mixed practice.
← All Class 7 Science chapters