Partial molal volumes of MgCl2, CaCl2, SrCl2, and BaCl2 in aqueous solution to 200°

Abstract

From precise density measurements to 200° on aqueous solutions of magnesium, calcium, strontium, and barium chlorides, the partial molal volumes of the salts, ϕ° were calculated. The values of ϕ° pass through a maximum at temperatures ranging from about 30° for MgCl₂ to 60° for SrCl₂ and BaCl₂. A useful correlation of electrostriction-volume loss V^e for both the alkali and alkaline earth ion series is given by a new empirical equation V^e=A′z/, where = 1·38 + ion radius. Values of A′ are reported for the temperature range 25–200°, and should prove useful in estimating the partial molal volume of other uni- and bi-valent spherical ions.