Why does the temperature of the water stay the same when it melts and boils

Heya user☺☺

This is because when it boils or melts it goes a change in its state and the heat which is provided to it is used to change the state instead of temperature therefore the temperature during boiling and melting remain unaffected.
The heat thus provided to the water is known as latent heat to which you can also call hidden heat.

This heat is different for melting and boiling.

Hope this will help☺☺

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