Calculate the standard free energy change for the following reaction $Zn(s) + Cu^{2+} (aq) \rightarrow Cu(s) + Zn^{2+} (aq)$ Given that $\Delta G_f^{\circ}\: for \: Cu^{2+} (aq)\: and \: Zn^{2+} (aq)$ as 65 kJ/mol and -147.2 kJ/mol respectively.

Question

$\begin {array} {1 1} (A)\;212.2\: kJ & \quad (B)\;-212.2 \: kJ \\ (C)\;82.2\: kJ & \quad (D)\;-82.2\: kJ \end {array}$