Question

What happens to the temprature of water when it boils

Answer 1

Conversion of water into steam is simply a phase change. This occurs due to the weekening of the intermolecular forces between the various water molecules.

Now as we supply heat to water at normal temperature, its temperature rises. As soon as the temperature reaches to the boiling point of the water at a particular pressure (please note that the boiling point of fluid is also function of pressure), the heat which is being supplied starts to get used up in weekening of the intermolecular forces and so the temperature of the water becomes constant. Throughout the phase change, the temperature remains constant. And when the water is completely converted to steam, the temperature again starts to rise.

So, during phase change there is no rise of temperatureas the heat supplied is getting used up as the Latent Heat of Vaporisation.