If pK_(b) for fluoride ion at 25^(@)C is 10.83, the ionisation constant of hydrofluoric acid at this temperature is

If pK_(b) for fluoride ion at 25^(@)C is 10.83, the ionisation constan

1.	If pK_(b) for fluoride ion at 25^(@)C is 10.83, the ionisation constant of hydrofluoric acid at this temperature is
Answer» `1.74xx10^(-5)` `3.52 xx 10^(-3)` `6.75 xx 10^(-4)` `5.38xx10^(-2)`. SOLUTION :The DISSOCIATION constants of a WEAK acid and its conjugate base arerelated as ` pK_(a)+pK_(b)=pK_(w)` `:. pK_(a)+10.83=14 "or " pK_(a)=3.17` `- log K_(a)=3.17` or log `K_(a)=-3.17=bar(4).83 "or" K_(a)=6.76xx10^(-4)`.