The Table describes four changes, A, B, C and D.
Table
| Change | Description |
|---|---|
| A | butter melts in a warm pan |
| B | bread is toasted until it turns brown |
| C | water vapour condenses on a cold window |
| D | a match burns |
Which two changes are physical changes?
Describe how a physical change is different from a chemical change.
A sealed bag contains 45 g of solid chocolate. The bag is warmed until all of the chocolate melts.
State the mass of the melted chocolate. Give a reason for your answer.
44 exam-style questions on OCR GCSE Physics 1.2 Changes of state, covering 1.2.1 Conservation of mass during changes of state, 1.2.2 Physical and chemical changes, 1.2.3 Heating, temperature and changes of state, 1.2.4 Specific heat capacity and specific latent heat, 1.2.5 Internal energy and temperature change, and 1.2.6 Energy transfer during a change of state. Each one has a worked solution and a mark scheme showing where the marks go.