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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
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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