Question

what is meant by saying that the latent heat of vaporisation of water is 22.5 into 10 to the power 5 J/kg

Answer 1

it means by applying 22.5into 10 to the power 5 J/kg the liquid change into vapour.

Answer 2

It means that the heat is required to change 1 kilogram of water (at its boiling point 100°c) to steam at the same temperature of 100°c