An ideal monoatomic gas undergoes a reversible process: , from (2 bar, 273 K) to 4 bar. The value of — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

$P/V = \text{constant} \implies PV^{-1} = \text{constant}$. This is a polytropic process with $n = -1$. Work done is $W_{by} = \frac{n_{mol} R \Delta T}{1 - n} = \frac{n_{mol} R \Delta T}{1 - (-1)} = \frac{1}{2} n_{mol} R \Delta T$. For a monoatomic gas, $\Delta U = \frac{3}{2} n_{mol} R \Delta T$. The ratio $\frac{\Delta U}{w} = \frac{3/2}{1/2} = 3.0$.