ISSN:
1572-8927
Keywords:
Activity coefficients
;
deuterio-o-phthalic acid
;
deuterium oxide
;
dissociation constants
;
electrochemical
;
emf
;
isotope
;
potassium hydrogen phthalate
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The first and second dissociation constants of deuterio-o-phthalic acid in deuterium oxide have been determined by the emf method over the temperature range of 5 to 50°C. The pD values for potassium deuterium phthalate have been calculated from these two constants and experimentally verified. The thermodynamic properties for the dissociation of deuterio-o-phthalic acid have been evaluated. At 25°C, these values in the molality scale are: pK 1A =3.505, pK 2A =5.890, and pD=4.518. From K 1A and K 2A , respectively: ΔG o =20.003, 33.582 kJ-mol−1; ΔH o =2.851, 2.208 kJ-mol−1; ΔS o =−76.7, −105.2 J-mol−1-K−1; and ΔC p o =−52.7, −315.6 J-mol−1-K−1. The isotope effect is discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00644891
Permalink
