Water, initially (state 1) a saturated liquid at 1100C, is contained in a piston-cylinder assembly. The water undergoes a process to the corresponding saturated vapor (state 2), during which the piston moves freely in the cylinder. If the change of state is brought about by heating the water as it undergoes an internally reversible process at constant pressure and temperature, determine: (a) heat transfer using first law of thermodynamics in kJ/kg and
(b) heat transfer using second law of thermodynamics in kJ/kg.