the constant pressure heat capacity of a sample of a perfect gas was found to vary with pressure according to the expression Cp/(JK)=20.17+O.4001T. calculate, q,w, changeinU and change in H

You would be correct, boiling water does disinfect contamination.    the property of disinfecting means to kill  germs, bacteria and other pathogens or contamination  that might cause an infection or cause a person to become sickly. a couple methods of disinfecting are using soap, other cleaning supplies or by simply "boiling" the contaminate.  the reason why boiling water disinfects certain attributes is because some cells cannot survive the heat and pressure.

The phase where ice changes directly to gas is called sublimation