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Question
Give the main differences between physical changes and chemical changes.
Solution
Important differences between a physical and a chemical change are given below:
| PHYSIAL CHANGE | CHEMICAL CHANGE |
| 1. No new substance is formed. | 1. A new substance is formed. |
| 2. Physical change is reversible. | 2. Chemical change is usually irreversible. |
| 3. It is a temporary change. | 3. It is a permanent change. |
| 4. No heat energy is evolved or absorbed. | 4. Heat energy is evolved or consumed in a large amount. |
| 5. Examples: Melting of ice, formation of clouds, tearing of cloth etc. | 5. Examples: Rusting of iron, ripening of fruits, cooking of food etc. |
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