Question

define the term (a) latent heat of fusion (b) latent heat of vaporiasation

Answer 1

(a). The enthalpy of fusion of a substance, also known as (latent) heat of fusion, is the change in its enthalpyresulting from providing energy, typically heat, to a specific quantity of the substance to change its state from a solid to a liquid, at constant pressure.

(b). Latent heat of vaporizationis a physical property of a substance. ... When a material in liquid state is given energy, it changes its phase from liquid to vapor; the energy absorbed in this process is called heat of vaporization. The heat of vaporization of water is about 2,260 kJ/kg, which is equal to 40.8 kJ/mol.

Answer 2

Latent heat of fusion is the amount of energy required by the surrounding to change liquid state to solid state ( water to ice ).
latent heat of vapourisation is the amount of heat energy required by the surrounding to change liquid state to gaseous state ( Evaporation).