For a gas phase cracking reaction $A{\rightarrow}B+C$ at $300^{\circ}$, the Gibbs free energy of the reaction at this temperature is $\Delta G^{\circ}=-2750$ $J$/mol. The pressure is $1$ bar and the gas phase cae be assumed to be ideal. The universal gas constant $R=8.314$ $J$/mol.$K$. The fractional molar conversion of $A$ at equilibrium is :

1. $0.44$
2. $0.50$
3. $0.64$
4. $0.80$