📖 Theory & Concepts ▼

1. Physical vs Chemical Changes

Property Physical Change Chemical Change
New substance Not formed Formed
Reversibility Usually reversible Usually irreversible
Energy change Small Large (heat/light)
Composition Unchanged Changed
Example Melting ice Burning Mg ribbon

2. Signs of Chemical Change

  • 🎨 Color change — CuSO₄ blue → white
  • 💨 Gas evolution — CO₂ from vinegar + soda
  • 🔥 Heat/Light — Mg burns with bright light
  • ⬇️ Precipitate — Solid formed in solution
Did you know? Copper sulphate pentahydrate (CuSO₄·5H₂O) loses its blue color when heated because the water molecules responsible for the color are released as steam!

🎯 Objective

To perform various reactions and classify them as physical or chemical changes by observing:

  • Color change
  • Gas evolution
  • Temperature change
  • Formation of precipitate
  • Reversibility of the change
Select Experiment
> Click "Heat" to start heating the blue copper sulphate crystals.
Action Feedback
CuSO₄·5H₂O (Blue crystals)

Key Concepts

Physical Change
No new substance formed. Reversible. No change in composition.
Chemical Change
New substance formed. Usually irreversible. Change in composition.
Lab Notebook
Observations will appear here...