In the investigation of the chemical reactions between metal ions and dialkylcliosimes, information concerning the influence of the alkyl groups on certain properties of the diosimes and their metal salts, e.g. solubility, distribution between organic solvents and aqueous solution, acid dissociation constants and complex formation constants, is of considerable importance analytically. Of the lower dialkyldiosimes, i.e, dimethylglyoxime (DMG), etl~ylmethylglyosime (ElMG) and diethylglyoxime (DEG), only DMG has been studied extensively1 12 and only some of the properties mentioned above have been determined for EMG and DEGs.4.
The aim of the present investigation was to determine solubility constants, distribution constants between organic and aqueous solutions and acid dissociation constants for EMG. A study of its complexes with copper and nickel will follow.
The UV spectra between zro-2go nm were also measured and resolved into their components. This was carried out in order to compare the results with the theoretical calculations on DMG spectra published by Roosb.
Chemicals
The ethylmethyl@yoxime was prepared by the method of BELCHER et al.'! and was recrystallized 3 times from water--alcohol mixtures. The chloroform (Merck, pa.) was washed 3 times with distilled water to remove alcohol and to saturate the solvent with water. The sodium perchlorate was prepared by a technique used at KTH, Stockholm7. All other chemicals were of analytical grade. The organic solvents were saturated with water before use. The ionic strength of the aqueous phase was kept constant at 0.x M.
Spectrophotometric
determinations of EMG were performed with a Beckman DB or DU spectrophotometer. The UV spectra of EMG at different PH were measured on a Perkin-Elmer Hitachi x3g spectrophotometer with a photomultiplier amplifier, quartz x-cm cells being used in all cases. The PH measurements were performed with a Beckman Research PH meter, a Beckman glass electrode 41260 type E-2 and a Beckman frit junction calomel electrode 3907x. In the solubility experiments the PH meter was .4?ral. Clrinr. Ada. 43 (1&S) 53-62