W. Eckert, ELECTROCHEMICAL IDENTIFICATION OF THE HYDROGEN-SULFIDE SYSTEM USING APH(2)S(GLASS AG-O,AS(2)S) ELECTRODE/, Journal of the Electrochemical Society, 145(1), 1998, pp. 77-79
Citations number
27
Categorie Soggetti
Electrochemistry,"Materials Science, Coatings & Films
An electrochemical method to simultaneously assess the two apparent di
ssociation constants of the hydrogen sulfide system at pH values rangi
ng from 6 to 11 is presented. pH(2)S and pS(2-) values were measured i
n aqueous solutions of known total sulfide concentrations using a silv
er sulfide/glass and a silver sulfide//silver chloride cell, respectiv
ely, and calculated the apparent dissociation constants directly from
the measured electrode readings. The measured constants (pK(al)' 6.91
+/- 0.05 and pK(a2)' 13.86 +/- 0.05) correspond well to those estimate
d through thermodynamic considerations. The controversy on the second
dissociation constant is discussed.