Consider the following equilibrium:

$3$I$2($g$)+6$F$2($g$)2$IF$5($g $)+$ I$4$F$2($g$)$

At a certain temperature, $6\mathrm{.}00$ mol of IF$5($g$)$ are added to a $5\mathrm{.}00$ L container. At equilibrium, $6\mathrm{.}00$ mol of I$4$F$2($g$)$ are left. Calculate the Keq for the reaction.