Illustrated Glossary of Organic Chemistry

Equilibrium constant (K_eq): A ratio that quantifies the position of a chemical equilibrium. When the equilibrium favors reactants ΔG > 0 and K_eq < 1. When the equilibrium favors products ΔG < 0 and K_eq > 1.

A generic equilibrium, and equilibrium constant expression.

Equilibrium constant expression for a mechanism step involving the ionization of tert-butyl bromide to form tert-butyl carbocation and bromide ion.