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प्रश्न
Name a chemical change which takes place in presence of:
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उत्तर
Heat:
- Burning of paper.
- Cooking of food need heat.
Light :
- Formation of food by plants i.e. photosynthesis need light.
- Hydrogen and chlorine react in presence of light
Electricity:
- Water breaks into hydrogen and oxygen on passing electricity.
- Sodium chloride solution breaks up into its components sodium and Chlorine on passing electric current through sodium chloride solution.
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संबंधित प्रश्न
Match the columns
| column A | coulmn B |
| 1. A change which cannot be easily reversed | a. man-made change |
| 2.A change that repeats itself at regular intervals | b. chemical change |
| 3. A change that is made by humans | c. physical change |
|
4. A change in which the original substance cannot be obtained |
d. periodic change |
| 5. A change where no new substance is formade | e. irreversible change |
| f. slow change |
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