THERMODYNAMICS OF THE DISSOCIATION OF BORIC-ACID IN SEAWATER AT S=35 FROM 0-DEGREES-C TO 55-DEGREES-C

The stoichiometric dissociation constants of boric acid in seawater at S = 35 have been determined from 0 to 55 degrees C. The constants wer e determined from electromotive force measurements made with the cell, Pt\H-2 (g, 1 atm) borax in synthetic seawater\AgCl, Ag. The results a re discussed in terms of ''total'' hydrogen ion scale. Our results are in excellent agreement (+/-0.0004 in In K+) with the measurements of Dickson (1990a). This study demonstrates that the measurements made by Dickson (1990a) are more reliable than the earlier measurements (Buch , 1933; Lyman, 1956; Hansson, 1973b) and should be used in all future studies of the carbonate system in seawater.