The proton-transfer reaction occurring to reach equilibrium when an acid or base is dissolved in water produces the conjugate of the dissolved acid or base. Thus one member of the conjugate pair is the reactant and the other is the product.
The
extent to which a reaction occurs is expressed as a percentage and is given by
| reaction extent | = | product concentration | × | 100% |
| initial reactant concentration |
The extent of reaction of
strong acids and bases with water is 100%.
The common strong acids are HNO3, H2SO4, HCl, HBr, HI, HClO4 and HClO3.
Strong bases are H–, N3–, S2–, O2–, OH– and alkoxide ions like CH3O–,
The extent of reaction of
weak acids and bases is less than 10%.
Common acids other than those listed above are weak.
Conjugates of weak acids are weak bases.