The balanced equation for the reaction is
CO(g) + 2H₂(g) ⇄ CH₃OH(g)
The given concentrations are at equilibrium state. Hence we can use them directly in calculation with the expression for the equilibrium constant, k. expression for k can be written as
k = [CH₃OH(g)] / [CO(g)] [H₂(g) ]²
[H₂]=0.072 M
[CO]= 0.020M
[CH₃OH]= 0.030 M
From substitution,
k = 0.030 M / 0.020 M x (0.072 M)²
k = 289.35 M⁻²
Hence, equilibrium constant for the given reaction at 700 K is 289.35 M⁻².
