To determine the equilibrium constant expression for a given reaction, let's first review the general form of the balanced chemical equation:
[tex]\[
a A + b B \rightleftharpoons c C + d D
\][/tex]
The equilibrium constant, [tex]\( K_{eq} \)[/tex], is defined based on the concentrations of the reactants and products at equilibrium. Specifically, it is the ratio of the product of the concentrations of the products raised to their respective coefficients to the product of the concentrations of the reactants raised to their respective coefficients.
For the given balanced equation:
[tex]\[
a A + b B \rightleftharpoons c C + d D
\][/tex]
The equilibrium constant expression [tex]\( K_{eq} \)[/tex] is:
[tex]\[
K_{eq} = \frac{[C]^c [D]^d}{[A]^a [B]^b}
\][/tex]
Where:
- [tex]\([A]\)[/tex], [tex]\([B]\)[/tex], [tex]\([C]\)[/tex], and [tex]\([D]\)[/tex] represent the molar concentrations of the reactants A and B and the products C and D, respectively.
- [tex]\(a\)[/tex], [tex]\(b\)[/tex], [tex]\(c\)[/tex], and [tex]\(d\)[/tex] represent the stoichiometric coefficients of the reactants and products in the balanced chemical equation.
Therefore, after reviewing the options provided, the correct equilibrium constant expression for the given system is:
[tex]\[
K_{eq}=\frac{[C]^c[D]^d}{[A]^a[B]^b}
\][/tex]
