• question_answer A polyatomic gas with six degrees of freedom does 25 J of work when it is expanded at constant pressure. The heat given to the gas is A) $100\text{ }J$                 B)        $150\text{ }J$                 C) $200\text{ }J$                 D)       $250\text{ }J$

[a] $dW=25=P({{V}_{2}}-{{V}_{1}})=nR({{T}_{2}}-{{T}_{1}})$ $dQ=dU+dW-n{{C}_{v}}dT+25$ $=n.\frac{R}{\gamma -1}({{T}_{2}}-{{T}_{1}})+25$ $=\frac{25}{\frac{4}{3}-1}+25=100J\left\{ \gamma =\frac{f+2}{f}=\frac{6+2}{6}=\frac{4}{3} \right\}$