The Standard Entropies of the Aqueous Lithium and Fluoride Ions and

STANDARD ENTROPIES OF AQUEOUSLITHIUM AND FLUORIDE IONS

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The Standard Entropies of the Aqueous Lithium and Fluoride Ions and the Heat of Solution of Lithium Fluoride'

by Clark C. Stephenson, Department of Chemistry, Massachusetts Institute of Technology, Cambridge $9,Massachusetts

Harry P. Hopkins, and Claus A. Wulff Department of Chemistry, Carnegie Institute of Technologg, Pittsburgh 1.3, Pennsylcania (Received December 20, 19/38)

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The literature contains two discordant values, 4.7 :k 1.0 and 2.5 f 0.3 cal./niole O R . , for the standard entropy of the aqueous lithium ion, based on the solution thermocheinistry of Li2COaand LiOH, respectively. Confirmation of the latter value would determine the standard entropy of the aqueous hydroxide ion and permit a choice between the two values reported for the heat of ionization of water. Reported herein are a calculation of the standard entropy of the aqueous lithium ion, from literature data for LiClaH20,as 2.5 f 0.3 cal./mole OK., and a value of 3.0 f 0.4 cal./mole 'I