$4-(\frac{25}{100})$ Stoichiometric amounts of nitrogen and hydrogen and $($:$3(mol)H_2\}$ are feed to a reactor, standard free energy change $($Gibbs Free Energy$)$ of reaction at $700K$ and $20$ bar given as $-53531\frac{J}{m}ol$ determine equilibrium constant $(K)$ and the percent conversion of nitrogen to ammonia $($extent of reaction$).$

$N_2+3H_2$harr$2N{H}_3$