What is the role of heat in evaporation?

Correct answer: Heat helps water become vapour

Direct answer: A, heat helps water become vapour. In liquid water, molecules are always moving, but they have different amounts of energy. When heat is supplied, many molecules move faster; some surface molecules gain enough energy to escape the liquid and enter the air as water vapour. This is evaporation, and it can occur below the boiling point. A correctly describes heat as an energy source that supports the liquid-to-gas change. B is wrong because heating does not turn water into stone. C is unrelated to evaporation and has no physical basis. D is wrong because heat strongly affects the rate of evaporation, although wind, humidity, and exposed surface area also matter. More heat usually speeds evaporation, while cooling favours condensation. Memory cue: heat gives water molecules the energy needed to escape from the liquid surface.