Question

What is the equilibrium constant dependent on?

Answer 1

Equilibrium constant:

1. This is expressed as the concentration of products divided by the concentration of reactants, each term being raised to the stoichiometric coefficient.
2. For example, $\mathrm{aA}+\mathrm{bB}\rightleftharpoons \mathrm{cC}+\mathrm{dD}$, where a, b, c, and d are the stoichiometric coefficients of the reactants A, B, C, and D. The expression for the equilibrium constant of the given reaction is:

$\mathrm{K}=\frac{{\left[\mathrm{C}\right]}^{\mathrm{c}}{\left[\mathrm{D}\right]}^{\mathrm{d}}}{{\left[\mathrm{A}\right]}^{\mathrm{a}}{\left[\mathrm{B}\right]}^{\mathrm{b}}}$

Parameters affect the equilibrium constant:

1. Equilibrium constants are temperature-dependent, independent of reaction quantities, catalysts, and inert materials. Moreover, it is independent of concentrations, pressures, or volumes of reactants.
2. The temperature dependence of the equilibrium constant is generally determined by $∆\mathrm{H}$ of the reaction.
3. As the temperature increases, the equilibrium constant for an exothermic reaction ($-∆\mathrm{H}$) decreases.
4. For the endothermic reaction ($+∆\mathrm{H}$), the equilibrium constant increases as the temperature increases.