In a turbine air expands from 5 bar, 520°C to 1 bar, 300°C. During expansion 10 kJ/kg of heat is lost to the surroundings which is at 0.98 bar, 20°C. Neglecting kinetic and potential energy changes, determine per kg of air:
(i) The decrease in availability;
(ii) The maximum work;
(iii) The irreversibility.
For air take: c p = 1.005 kJ/kg K ; h = c p T, where c p is constant.