For the reversible reaction, ${{\rm{N}}_2}\left( {\rm{g}} \right) + 3{{\rm{H}}_2}\left( {\rm{g}} \right)\leftrightharpoons2{\rm{N}}{{\rm{H}}_3}\left( {\rm{g}} \right)$ at $500^\circ C$, the value of ${K_p}$ is $1.44 \times {10^{ - 5}}$ when partial pressure is measured in atmospheres. The corresponding value of ${K_c}$ with concentration in ${\rm{mol}}\;{{\rm{L}}^{