For the reaction N2 + 3H2 gives 2NH3, the equilibrium constant expression Kc is
- A. [N2][H2]^3 divided by [NH3]^2
- B. [NH3] divided by [N2][H2]
- C. [NH3]^2 divided by [N2][H2]^3
- D. 2[NH3] divided by [N2] + 3[H2]
Explanation
Kc is written as the product concentrations over the reactant concentrations, each raised to the power of its coefficient in the balanced equation. Inverting the expression gives the equilibrium constant for the reverse reaction, which is why the first option is offered. Coefficients become exponents, never multipliers, which rules out the last option.