title: Solubility and protonation of EDTA, DCTA and DPTA in acidic perchlorate medium.
abstract: From measurements of solubility as a function of pC(H), the protonation constants of EDTA, DCTA and DTPA for the first dissociation and addition steps have been determined. The following values were found: EDTA: log k(6) = -0.10 +/- 0.05, log k(5) = 1.45 +/- 0.02, log k(4) = 1.95 +/- 0.02 and log k(3) = 2.50 +/- 0.03; DCTA: log k(5) = 1.78 +/- 0.02, log k(4) = 2.30 +/- 0.02 and log k(3) = 3.50 +/- 0.03; DTPA: log k(7) = 0.75 +/- 0.03, log k(6)= 1.22 +/- 0.02 and log k(5) = 2.08 +/- 0.02. The experiments were done in acidic perchlorate medium (I = 1.0) at room temperature (21 degrees ).
authors.affiliation: Natuurkundig Laboratorium der Universiteit van Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Kragten
authors.forename: L G
authors.initials: LG
authors.lastname: Decnop-Weever