Derive an expression for ionisation constant for ionisation of a weak acid and its degree of ionisation?
An acid or base's strength refers to its degree of ionization. A strong acid will completely ionize in water while a weak acid will only partially ionize.
Since there are different degrees of ionization, there are different levels of weakness. Fortunately, there is a simple quantitative way of expressing this.
Since the ionization of a weak acid is an equilibrium, a chemical equation and an equilibrium constant expression can be written:
The equilibrium constant for the ionization of an acid is called the acid ionization constant (Ka)