ISSN:
1572-8927
Keywords:
1-1 Electrolytes
;
DMSO
;
density
;
ultrasonic vibration potential
;
ionic partial molal volumes
;
solvation
;
electrostriction
;
steric hindrance
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The partial molal volumes of Li+, Na+, K+, Rb+, Cs+, Cl−, Br−, I−, and NO 3 - in DMSO at 25°C have been determined from ultrasonic vibration potential data and density data for solutions of uni-univalent electrolytes. Hepler's semiemprirical equation has been used to split ionic partial molal volumes into geometric and electrostrictive contributions. The results obtained in this work confirm the conclusion of our previous studies, namely, that the contribution of electrostriction is essentially determined by the properties of that layer of atoms, 0.3 to 0.4 nm thick, in contact with the ion and by the degree of steric hindrance of the poles of the dipole of the solvent molecule. On the other hand, the geometric contribution depends on the size of the solvent molecule and also on the arrangement of the solvent molecules about the ions. It is shown that the geometric contribution to the partial molal volume of ions is largely increased when ions cannot come close enough to the poles of the solvent-molecule dipole, owing to steric hindrance.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00650450
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