$VT=$constant

$V(p V)=$ constant

$\therefore p V^{2}=$ constant

In the process $p V^{x}=$ constant, molar heat capacity is

$C=\frac{R}{\gamma-1}+\frac{R}{1-x}$

Here, $x=2$

$\therefore C=\frac{R}{\gamma-1}+\frac{R}{1-2}=\left(\frac{2-\gamma}{\gamma-1}\right) R$

Now, $Q=n C \Delta T$

$=(1)\left(\frac{2-\gamma}{\gamma-1}\right) R \Delta T$

$=\left(\frac{2-\gamma}{\gamma-1}\right) R \Delta T$