Chapter 14, Problem 14.9P

For the ammonia synthesis reaction written:

$\frac{1}{2}{N}_2\left(g\right)+\frac{3}{2}{H}_2\left(g\right)\to N{H}_3\left(g\right)$

with 0.5 mol $N_2$ and 1.5 mol $H_2$ as the initial amounts of reactants and with the assumption that the equilibrium mixture is an ideal gas, show that:

${\in }_e=1-{\left(1+1.299K\frac{P}{P°}\right)}^{-1/2}$