The enthalpy of a real gas, in general, depends on the pressure as well as on the temperature. devise a way to evaluate the change in enthalpy of a real gas associated with a change of state from (t1,p1) to (t2,p2). describe in a t-s diagram how you would find enthalpy changes.

10 kg of co2 is initially contained at 400 kpa and 300 k. the gas constant for carbon dioxide is 189 j/lkg k) and has a specific heat ratio, k, of 1.289. isentropic expansion then occurs until the pressure is 200 kpa. a) determine the initial volume of co2 in m. b) determine the final temperature in k. c) determine the work done by the system during the expansion kl.