Topic Details (Notes format)

Changes Around Us

Subject: General Science

Book: NCERT Science Class 6

Changes occur everywhere around us and can be classified as:
- **Reversible changes**: Can be reversed (example: melting of ice).
- **Irreversible changes**: Cannot be reversed (example: burning of paper).
- **Physical changes**: No new substance is formed (example: tearing of paper).
- **Chemical changes**: A new substance is formed (example: rusting of iron).
- **Applications in daily life**: Cooking involves chemical changes, freezing water is a physical change.

**Possible Exam Questions:**
1. Define reversible and irreversible changes with examples.
2. How is rusting of iron an example of a chemical change?
3. Explain the difference between physical and chemical changes.
4. Why is cooking considered an irreversible change?
5. Discuss the importance of reversible changes in industrial applications.

Practice Questions

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