Reversible reaction
From Wikipedia, the free encyclopedia
A reversible reaction is a chemical reaction that may proceed in both the forward and reverse directions. In other words, the reactant and product of one reaction may reverse roles, without adding chemicals.
Symbolically,
- aA + bB ⇌ cC + dD
products C and D are produced from reactants A and B, but C and D can react to form A and B.
In an irreversible reaction the equilibrium states are shifted so close to either the products or the reactants that the reaction effectively does not have an equilibrium between the products and the reactants. Hence, irreversible reactions can be viewed as an extreme, "special case" of reversible reactions. Irreversible reactions are often called "spontaneous" or "favorable". These reactions are usually entropically driven, as opposed to thermodynamically driven. In an irreversible reaction, there is generally a great increase in entropy.
