...

Consider one mole of an ideal gas at a temperature of 298 K and pressure of 1 bar, for which Cp.m = 20.78) K mol-1 Calculate the change in entropy of the system (45) and surroundings (AS surr), for the following transformations: (a) An adiabatic expansion into a vacuum, to double the initial volume. (b) A reversible, isothermal expansion, to double the initial volume (c) Heating to 400 K at a constant pressure of 1 bar. Take the temperature of the surroundings to be constant at 400 K