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प्रश्न
Classify the following changes as physical and chemical changes
A rough piece of wood is sanded and polished resulting in change in texture, Rusting of a iron nail, Painting the grill, Bending a paper clip, Pounding silver into thin plate, Rolling the chappathi dough into thin wire, Occurrence of day and night, eruption of volcano, burning of matchstick, dosa from the batter, blinking of eyelids, occurrence of a thunderstorm, rotation of the earth, formation of eclipses.
| Sr. No. | Physical changes | Chemical changes |
| 1. | ||
| 2. |
उत्तर
| Sr. No. | Physical changes | Chemical changes |
| 1. |
Bending a paper clip. |
Rusting of a iron |
| 2. |
Pounding silver into thin plate. |
Eruption of volcano |
| 3. |
Rolling a chapathi dough into thin wire. |
Burning of matchstick. |
| 4. |
Occurrence of a day and night. |
|
| 5. |
Blinking of eyelids. |
|
| 6. |
Occurrence of a thunderstorm. |
|
| 7. |
Rotation of the earth. |
|
| 8. |
Formation of eclipses. |
|
| 9. |
Painting the grill. |
|
| 10. |
A rough piece of wood is sanded and polished resulting in change in texture. |
|
| 11. |
Dosa from the batter. Dosa from the batter. |
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संबंधित प्रश्न
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Down
1 . It is the change that takes place in case of swinging pendulum of a clock. –
2. Occurrence of this is a non-periodic change as well as a natural change.
3. It is a physical change.
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| Sr. No. | A | B | C |
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| 2. | Condensation | Change of state from liquid to gas | Formation of ice cube |
| 3. | Evaporation | Change of state from solid to liquid | Collecting flowers |
| 4. | Freezing | Change of state from gas to liquid | Ice cube to water |
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| 6. | Non-periodic change | Occurs at regular time intervals | Steam to water drops |
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Assertion: Burning of wood log to charcoal is a physical change.
Reason: The products formed of burning a piece of wood can be easily converted back to wood log.
