Air is compressed from an initial condition of 1 bar and 25°C to a final state of 5 bar and 25°C by three different mechanically reversible processes in a closed system: ?

    (a) Heating at constant volume followed by cooling at constant pressure. ?

    (b) Isothermal compression. ?

    (c)Adiabatic compression followed by cooling at constant ?volume. ?

    Assume air to be an ideal gas with the constant heat capacities, CV= (5/2)R and CP = (7/2)R. Calculate the work required, heat transferred, and the changes in internal energy and enthalpy of the air for each process. ?