Question

why does the temperature of a substance remains constant during its melting or boiling point​

Answer 1

as the heat energy supplied goes in breaking the bonds present between two atoms or molecules during melting and boiling.

Answer 2

The temperature of a substance remains constant during it's melting or boiling point because the energy is used in overcoming the forces of attraction between it's particles. This is known as latent heat. The word 'latent' means hidden.

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