Question

A liquid is being converted into steam at its boiling point what will be specific heat of liquid at this time

Answer 1

The boiling point or the matter state change process will be isothermal in nature. That is, the temperature won't change  throughout the time of state change process. That is valid for all state evolving forms (sold to fluid and liquid to gas).  

In the mean time, Specific Heat is the measure of heat required to raise the temperature by 1 degree.  

{(Tf-Ti) =1 }  

C=Q/(Tf-Ti)               (Unit : Kilo Joules/Celsius)  

So the Specific Heat will be equal to C=Q/(Tf-Ti)