Question

The melting point and the freezing point of a substance are equal. Why?

Answer 1

1. The melting point is the temperature at which solid changes into a liquid phase.
2. The freezing point is the temperature at which a liquid changes into its solid phase.
3. It means that freezing and melting are the reverse processes.
4. As a given phase transition (whether direct or reverse) takes place at a fixed temperature, hence the melting point and the freezing point of a substance are always equal.