Same chapter1 markDifficulty: Medium
While a solid is melting at its melting point, the heat supplied:
Calorimetry
3 marksDifficulty: Medium
Why is a burn caused by steam at 100 °C more severe than one caused by water at 100 °C?
Original Khojo Papers practice question — not from a past board paper.
Answer
Steam at 100 °C gives out its latent heat of vaporisation, about 2260 J per gram, as it condenses on the skin, and only then does it cool as water. Water at the same temperature gives out only the heat lost in cooling. The extra latent heat makes the steam burn far worse.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Both are at the same temperature, so the difference is entirely one of energy given up, not of temperature.
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