title: The protonation and dimerization of 2,4-, 2,5-, 2,6-and 3,5-dihydroxybenzoic acids in 0.5M sodium perchlorate medium.
abstract: The protonation equilibria of 2,4-, 2,5-, 2,6- and 3,5-dihydroxybenzoic acids were studied by means of potentiometric titrations at I = 0.5 (NaClO(4)) and 25 degrees . The dimeric species H(6)L(2) and H(5)L(2) were found to form as well as the monomeric species H(p)L in the acidic solutions of 2,4- and 3,5-dihydroxybenzoic acids under the conditions studied. For the other two acids, the protonation scheme can be expressed exclusively in terms of the species H(p)L (p = 1, 2 or 3).
authors.affiliation: Department of Chemistry, University of Oulu, Linnanmaa, SF-90570 Oulu 57, Finland.
authors.forename: L H
authors.initials: LH
authors.lastname: Lajunen
authors.forename: J
authors.initials: J
authors.lastname: Saarinen
authors.forename: S
authors.initials: S
authors.lastname: Parhi