Question

for any substance why does the temperature remain constant during the change of state

Answer 1

during the change of state , the potential energy of the molecules changes ie the intermolecular distance changes. this change requires heat energy.

during the change of state the heat energy absorbed is required to change potential energy of the molecules and so it doesn't change the temperature of thr substance.

Answer 2

For any substance the temperature remain constant during the change of state because when the state of any substance change its potential energy changes due to change in position of molecules of that substance at the same time the heat is also absorbed during the change of state hence the change of heat and change in potential energy is equal due to this temperature remains constant.

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