问答题
Calculate the pH at which an acid indicator with Ka=1. 0×10-5 chan ges color when the indicator is 1.00×10-3 M.
【正确答案】The midpoint of the coIor change range of an indicator is the point at which its acid and conjugate base forms are present in equal concentration, hence KIn=[H3O+][In-]/[HIn]=[H3O+]=1.0×10-5 and pH=5.00