Question

Water as ice has a cooling effect, whereas water as steam may cause severe burns. Explain these observations.

A glass tumbler containing hot water is kept in the freezer compartment of a refrigerator (temperature < 0°C). If you could measure the temperature of the content of the tumbler, which of the following graphs (Fig.1.2) would correctly represent the change in its temperature as a function of time.

Conversion of solid to vapour is called sublimation. Name the term used to denote the conversion of vapour to solid.