For the cell reaction $2Fe^{3+}\left ( aq \right )+2l^{-}\left ( aq \right )\rightarrow 2Fe^{2+}\left ( aq \right )+l_{2}\left ( aq \right )$ $E^{\Theta }_{cell}=0.24 V$ at 298 K. The standard Gibbs energy $\left ( \Delta _{r}G^{\Theta }\right )$ of the cell reaction is : [Given that Faraday constant F = 96500 C $mol^{-1}$]