For the reaction ${\mathrm{H}}_2+{\mathrm{I}}_2\rightleftharpoons \underset{\left(\mathrm{g}\right)}{2\mathrm{HI}}$ at 721k the value of equilibrium constant ${\mathrm{k}}_{\mathrm{c}}$ is 50, the $\left(\mathrm{g}\right)\mathrm{ }\left(\mathrm{g}\right)$ value of ${\mathrm{k}}_{\mathrm{p}}$ under the same condition will be ___