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The paper p r e s e n t s a s t u d y o f t h e Ph,AsPh,B assumption a s f o r v e r i f i c a t i o n o f i t s p l a u s i b i l i t y f o r t h e d e t e r m i n a t i o n o f thennodynamic q u a n t i t i e s of s i n g l e ions i n mixed d i m e t h y l s u l f o x i d e (DMS0)-water s o l v e n t s . For d i s c u s s i o n t h e solv a t l o n e n e r g y is c o n s i d e r e d as a composite of e l e c t r o s t a t i c and n e u t r a l compon e n t s . The n e u t r a l components are r e p l a c e d by experimental d a t a of Ph,Ge and Ph,C which are proved t o b e e q u a l , o f t h e i r s i z e and s t r u c t u r e , t o t h e r e f e r e nce c a t i o n and anion. The electrostatic components are o b t a i n e d by c a l c u l a t i o n a c c o r d i n q t o t h e t h e o r y i n t h e l i t e r a t u r e . The results o f t h e p r e s e n t i n v e s t ig a t i o n p r o v i d e t h e c o n c l u s i o n t h a t an assymmetric p a r t i t i o n is p r e f e r r e d t o an e q u a l p a r t i t i o n p r a c t i c e d i n t h e l i t e r a t u r e . Baspd on t h e s t y d y , t h e s t a n d a r d f r e e e n e r q i e s of t r a n a f v r f o g s i n g l e i o n s and I-, are d e t e rmined and f o r o t h e r s , H , L i , N a , K , &+, C1-and B r -e v a l u a t e d from t h e d a t a o f s a l t s known i n t h e l i t e r a t u r e . Discussion is e l a b o r a t e d

The partitioning of thermodynamic quantities of the reference electrolyte (Ph4AsPh4B) is discussed by comparing its standard free energies of transfer from water to organic solvents (ΔWSG°) with those for Ph4AsPh4B. From experiment in 14 different dipolar‐aprotic organic solvents, it is found that an asymmetric partition with the ratio: ΔWSG° (Ph4As+)/ΔWSG° (Ph4B−)=1.08 ± 0.02 is better justified than the equal partition practised in the literature. This asymmetry is mainly ascribed to the size difference between the reference cation and anion. The electrostatic contribution (ΔWSG°A(el)), primarily from iondipole interaction, does not appear as a cause for the asymmetry.

Decay rate /Change of decay rate /' 5 Zn Summary The relative decay rate change, Δ λ/λ, of 65 Zn in its two oxidation states, Zn° and Zn 2 is determined by measuring gamma activities of a pair of samples alternately. The redox reaction of Zn is realized in a secondary battery at a certain time interval during the activity measurement. By using the so called "jumpmçthod" the Δλ/λ value for the given set of oxidation states is determined to be Δλ λ( 45 Ζη° ) -\(Ca 65 Zn(OH) 4 ) (11.5 ± 0.4) X 10-λ λ(« 5 Ζη°)The theoretical estimates made in this work corroborate approximately the experimental values.