Q.
2.5ml0.4(M) weak monoacidic base (kb=1×10−12. at 25∘C ) is titrated with 152(M)HCl in water at 25∘C. The concentration of H+at equivalence point is (kw=1×10−14, at 25∘C)
N1V1=N2V2( At equivalence point ) 0.4×2.5=152×V2 BOH(aq)+HCl(aq)→BCl−(aq)+H2O(I) ∴V2=1520.4×2.5 =20.4×2.5×15=7.5ml ∴ Concentration of salt =2.5+7.50.4×2.5
or, Salt of weak base and strong acid =0.1 ∴[H+]=Ch=KbKwC =10−1210−14×0.1=10−3 =3.2×10−2M
as Ch2=KbKw ∴h=KbCKw