what is the latent heat of vaporization ?

The latent heat a of vaporisation of a liquid is also called the latent heat of boiling of a liquid.

The quantity of heat required to convert one unit mass of a liquid into vapour at its boiling point without any change of temperature is called its latent heat of vaporisation.

The SI unit of the latent heat of vaporisation of a liquid is joule per kilogram (J/kg).

The latent heat of vaporisation of water is the amount of heat required to convert one unit mass of water into vapour at the boiling point of water (is at 100°C at 1 atm pressure).

The value of the latent heat of vaporisation of water in SI units is 22.6 x 10 J/kg. Thus to vaporise 1kg of water at 100°C into vapour at the same temperature, 22.6 x 10 Joules of heat energy is required.

As a result, therefore steam at 100°C is a more effective heating agent than water at the same temperature (is at 100°C).