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प्रश्न
Which of the following does not involve a chemical reaction?
विकल्प
digestion of food in our body
process of respiration
burning of candle wax when heated
melting of candle wax on heating
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उत्तर
melting of candle wax on heating
Explanation:
On heating, wax changes only its physical state (solid to liquid), not its properties. Hence, only physical change takes place.
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