Given the reaction between 2 gases represented by A_2 and B_2 to give the compound AB_( g ). A_2( g ) + B_2( g ) ⇌ 2 AB_( g ). At equilibrium, the…

Given the reaction between $\displaystyle 2$ gases represented by $\displaystyle \mathrm{A}_2$ and $\displaystyle \mathrm{B}_2$ to give the compound $\displaystyle \mathrm{AB}_{(\mathrm{g})}$. $$\mathrm{A}_{2(\mathrm{~g})}+\mathrm{B}_{2(\mathrm{~g})} \rightleftharpoons 2 \mathrm{AB}_{(\mathrm{g})} . $$ At equilibrium, the concentration $$\begin{aligned} & \text { of } A_2=3.0 \times 10^{-3} \mathrm{M} \\ & \text { of } B_2=4.2 \times 10^{-3} \mathrm{M} \\ & \text { of } A B=2.8 \times 10^{-3} \mathrm{M} \end{aligned} $$ If the reaction takes place in a sealed vessel at $\displaystyle 527$°C, then the value of $\displaystyle \mathrm{K}_{\mathrm{c}}$ will be :