Question

boiling point of a substance is foixed why explain?

Answer 1

Dear student!
Boiling point is the temperature at which the vapor pressure of liquid becomes equal to the surrounding pressure and the substance starts to boil.

Actually at this temperature the substance starts to change into its vapor so this temperature is always fixed as a substance need the fixed amount of heat energy to convert into vapor phase and this sufficient energy supplied is shown by the temperature called as boiling point.

So, the value of boiling point is fixed for a pure substance.