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Question
A person's skin is more severely burnt when put in contact with 1 g of steam at 100°C than when put in contact with 1 g of water at 100°C. Explain
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Solution
Steam has greater energy than boiling water due to latent heat of vapourisation. The internal energy of the vapour at 100 oC is greater than the internal energy of the boiling water at the same temperature. Thus, steam burns the skin more severely than boiling water.
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