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प्रश्न
Given reason:
Burning of paper is a chemical change.
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उत्तर
When a piece of paper is burnt a new substance ash is produced. Even when the burning is stopped, the ash cannot be changed back into paper. This shows that the formation of the ash from paper is a permanent and irreversible change.
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संबंधित प्रश्न
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Photosynthesis
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Classify the following changes as physical or chemical:-boiling
Tick (√) the correct alternative from the choice given for the following statement.
A substance which can not sublime is
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State when a substance [i.e. matter] undergoes a kind of change.
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Breaking of glass
