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प्रश्न
State the observations seen, when milk in a dish is kept aside for a few hours or more. Is the change which occurs – a physical change or a chemical change. Give reasons.
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उत्तर
On keeping aside – the milk in a dish for a few hours or more. The change observed – will be that the milk has changed into curd. The change is permanent and cannot be reversed. New substance curd is formed. It is a chemical change.
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