Coupled Equilibria
Two or more equilibria that share a common species, so that shifting one necessarily shifts the others.
Unit
Dimensionless
In depth
When equilibria are coupled, their constants multiply for the combined process, so a strongly favourable equilibrium can pull an unfavourable one forward by consuming its product. This is how complexation and acid–base chemistry can dissolve otherwise insoluble solids.
Examples in the real world
Adding acid dissolves CaCO₃ because carbonate is removed as CO₂, pulling the dissolution equilibrium forward.