(III) Consider an ideal gas of n moles with molar specific heats CV and CP. (a) Starting with the first law, show that when the temperature and volume of this gas are changed by a reversible process, its change in entropy is given by
(b) Show that the expression in part (a) can be written as
(c) Using the expression from part (b), show that if dS = 0 for the reversible process (that is, the process is adiabatic), then PVγ = constant, where γ = CP/CV.
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