thnx for the reply
But i don't think that we should find the heat vaporization for liquid and vapor state, because we didn't deal with such thing in class , but we do need to find the specific heat of the refrigerant-134a to be able to use the formula which i post above .
Refrigerant-134a is to be cooled by water in a condenser. The refrigerant enters the condenser with a mass flow rate of 6 kg/min at 1 MPa and 70oC and leaves at 35oC. The cooling water enters at 300 kPa and 15oC and leaves at 25oC. Neglecting any pressure drop, determine
(a) the mass flow rate...