Question

Determine `[overset(Θ)OH]` of a `0.050M` solution of ammonia to which sufficient `NH_(4) CI` has been added to make the total `[NH_(4)^(o+)]` equal to `0.1M`.

Answer 1

`NH_(3) + H_(2)O hArr NH_(4)^(o+) + overset(Θ)OH`
`K_(b) = ([NH_(4)^(o+)][overset(Θ)OH])/([NH_(3)])=((0.1)x)/((0.050)) = 1.8 xx 10^(-5)` thus
`x = [overset(Θ)OH] = 9.0 xx 10^(-6)`