calculation from literature values with standard SSA and SSD at ionic strength of 1M, log K for Aerosil in brackets for Cabosil content »Si-OH2<1+> + CN<1-> = »Si-OH2-CN logK = 1.6(1.4) »Si-OH + H<1+> = »Si-OH2<1+> -pK1 = logK = -1.4 sum »Si-OH + CN<1->+ H<1+> = »Si-OH2-CN logK = 1.6(1.4)-1.4 = 0.2(0.0)