Chapter 15, Problem 89AP

The equilibrium constant $K_c$ for the reaction:

${\text{H}}_{\text{2}}{\text{(g)+I}}_{\text{2}}\text{(g)}\stackrel{}{\rightleftarrows }\text{2H(g)}$

is 54.3 at $\text{430°C}$. At the start of the reaction, there are 0.714 mol of ${\text{H}}_2,$ 0.84 mol ${\text{I}}_{\text{2}}\text{,}$ and 0.886 mol of HI in a 2.40-L reaction chamber. Calculate the concentrations of the gases at equilibrium.