The equilibrium constant has been the ratio of the product and the reactant concentration raised to the stoichiometric coefficient. The equilibrium concentration of methane is 0.059 M.
The equilibrium can be defined as the condition in which the rate of formation of product and the rate of breakdown of product is equal.
The given reaction has been:
[tex]\rm CO+3\;H_2\;\leftrightharpoons\;CH_4+H_2O[/tex]
The equilibrium constant (kc) for the reaction has been given as :
[tex]k_c=\rm \dfrac{[CH_4][H_2O]}{[CO][H_2]^3}[/tex]
Substituting the values of the equilibrium concentration in the equation as:
[tex]k_c=\dfrac{[\text C\text H_4][0.020]}{[0.30][0.10]^3} \\\\3.90=\dfrac{[\text C\text H_4]\;\times\;0.020}{0.0003} \\\\\rm CH_4=0.059\;M[/tex]
The equilibrium concentration of methane is 0.059 M. Thus, option C is correct.
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