Question

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

Answer 1

The temperature of any substance remain constant during the change of state because the heat energy supplied is used up in changing the state of matter and also this heat is used for breaking of several bonds or attractive forces.

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Answer 2

because the temperature given is used to overcome the intetmolecular spaces for changing the state of matter .So the temperature is constant.
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