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प्रश्न
Explain in brief the involvement of energy in physical and chemical changes.
उत्तर
Involvement of energy in physical and chemical changes
- Physical changes use energy to change the state of matter,
- Chemical changes release or absorb energy when changing a substance into a new substance.
Energy is released during the decomposition of a substance while energy is absorbed during the formation of a new substance.
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संबंधित प्रश्न
What do you observe when :
solid ammonium chloride is heated
State whether the following is physical or chemical changes.
passing electric current through a heater rod —
Tick (√) the correct alternative from the choice given for the following statement
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Tick (√) the correct alternative from the choice given for the following statement
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True or false?
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Natural change and man-made change
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Under which different types can the following changes be classified?
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Give reason.
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Some changes are listed in the following table. For each change, write in the blank column, whether the change can be reversed or not.
| S. No. | Change | Can be reversed (Yes/No) |
| 1. | The sawing of a piece of wood | |
| 2. | The melting of ice candy | |
| 3. | Dissolving sugar in water | |
| 4. | The cooking of food | |
| 5. | The ripening of a mango | |
| 6. | Souring of milk |
