(d) Efficiency of a reversible Carnot engine (4%)

2. An ideal gas at 298.15 K and 1 bar is expanded in a reversible adiabatic process to a final pressure of 1/2 bar. Calculate $q$ per mol, $w$ per mole, and $\Delta U$. (assume: $Cv=\frac{3}{2}R$, $Cp=\frac{5}{2}R$) (10%)