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Matter in Our Surroundings — Science STD 9 — Question

CBSE BoardEnglish MediumSTD 9ScienceMatter in Our Surroundings3 Marks
Question
Why does our palm feel cold when we put some acetone (or perfume) on it?
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Answer

Acetone (or perfume) is volatile in nature. When we apply it to our palm, we feel cold. This happens due to the fact that to change from liquid to the vapour state, acetone requires latent heat of vaporization. Acetone takes this latent heat of vaporization from the hand due to which the palm loses heat and feels cold.

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