Question

On a hot summer day, we often put ice cubes to cool the water. Why?

Answer 1

Ice cubes cool the water because melting ice requires a large amount of heat energy, called latent heat of fusion. When ice cubes at 0°C are put into warm water, they absorb heat from the water to melt. Heat is absorbed by 1 kg of ice at 0°C to change into water at 0°C without any rise in temperature. This heat is taken from the warm water, so the water loses heat energy and its temperature falls. Thus, the water becomes cool. Also, the water formed by the melting ice is at 0°C, which mixes with the warm water and lowers its temperature further.