What is degree of ionization is respect of weak acids and weak bases? Derive the relationship between degree of ionization (`alpha`) and ionization constant `(K_(a))` for thke weak acid HX.

Explanation

Degreeof ionization: It can be defined as the fraction of acid (a) base that undergoes ionization per one mole of acid or base. For strong acids or bases degree of ionization `(alpha)` is equal to `1`.
Let's consider a weak acid HX with concentration 'c'. It unergoes partial ionization.
`HXhArrH^(+)+X^(-)`
Initial concentration c, 0, 0
Concentration at equilibrium `c(1-alpha), c alpha, c alpha`
Where `alpha` is degree of ionization
Ionization constant `K_(a)=([H^(+)][X^(-)])/([HX])`
`impliesK_(a)=((c alpha)(c alpha))/(c(1-alpha))` for weak acids `alpha lt lt 1`, so `alpha` is negligible.
`impliesK_(a)=(c^(2)alpha^(2))/cimpliesalpha=sqrt((K_(a))/c)`