Question

Assuming Ka for a monoprotic strong acid is 1

Answer 1

Ka * Kb = Kw

1 x 10^-6 * Kb = 1 x 10^-14

Kb = 1 x 10^-14 / 1 x 10^-6 = 1 x 10^-8

So, Kb for conjugate base of the srong acid = 1 x 10^-8

Conjugate bases of strong acids do not have basic properties on water because conjugate base of a strong acid is a very weak base whose basic properties are weaker than water that is water will be more basic than the weak base. So water will react as the base in a reaction containing water and a particular conjugate base of a strong acid. Hence we can say that the conjugate bases of strong acids have no basic properties in water.

Conjugate acid of LiOH = Li+ ion

Conjugate acid of KOH = K+ ion

Conjugate acid of RbOH = Rb+ ion

Conjugate acid of CsOH = Cs+ ion

Conjugate acid of Ca(OH)2 = Ca2+ ion

Conjugate acid of Sr(OH)2 = Sr2+ ion

Conjugate acid of Ba(OH)2 = Ba2+ ion

These cations won't have acidic properties in water because water will be more acidic than these cations hence water will participate in a reaction as the acid and not these cations.