_____ is the heat per unit mass required to change a substance from solid into liquid at the same temperature and pressure.

Question

Question

This question was previously asked in

RRB ALP Electrician 22 Jan 2019 Official Paper (Shift 1)

Answer 1

The correct answer is option 2 i.e Latent heat of fusion.

The latent heat of fusion is the heat per unit mass required to change a substance from solid into liquid at the same temperature and pressure.
- Latent heat of fusion is also known as the enthalpy of fusion.
- The latent heat of fusion of a solid is almost always positive in value.

Vaporisation	Conversion of a substance from the liquid or solid phase to the gaseous (Vapour) phase.
Regelation	Phenomenon of melting under pressure and refreezing again when the pressure is reduced.
Sublimation	Direct conversion of a substance from its solid state to the gaseous phase, without an intermediate liquid stage. Examples: Dry ice, solid CO₂, Iodine.