Question

For any substance, why does the temperature remain constant during the change of state?​

Answer 1

For any substance the temperature remains constant during the change of state because the heat energy which is supplied to change the state of matter is used in breaking the intermolecular forces and other attractive forces .

Answer 2

$\huge{ \underline{ \overline{ \mid{ \rm{ \red{Answer}} \mid}}}}$

It is due to the latent heat as the heat supplied to increase the temperature of the substance is used up to transform the state of matter of the substance hence the temperature stays constant.