CARRIERS IN ELECTROLYTIC SOLUTIONS 213 



tetramethylammonium hydroxide is a base whose strength is practically 

 the same as that of potassium hydroxide. The positive ions of the strong 

 organic bases possess distinct metallic characteristics in their compounds. 

 With a few exceptions, these ionic groups may not be obtained in a free 

 neutral state, since in this condition they are comparatively unstable, 

 yielding, as a rule, various neutral organic compounds. The tetramethyl- 

 ammonium group, as indeed the ammonium group itself, possesses an 

 appreciable stability. So, for example, the ammonium group forms an 

 amalgam in which the presence of the free ammonium group has been 

 established. 17 The tetramethylammonium group forms a stable, solid, 

 metallic amalgam with mercury, 18 and this group, moreover, may be pre- 

 cipitated in a free state by electrolysis in ammonia solution. 19 Under 

 these conditions the free group dissolves in ammonia to form a solution 

 which resembles solutions of the alkali metals in the same solvent. These 

 solutions, however, are relatively unstable so that their properties have 

 not been further investigated. 



The mercury group, CH 3 Hg, has been obtained in a free state by elec- 

 trolytic precipitation from an ammonia solution. 20 The free group is a 

 distinctly metallic substance which is a good conductor of the electric 

 current. This group, while relatively stable in comparison with other 

 groups, nevertheless reacts slowly, even at low temperatures, and at high 

 temperatures it reacts instantaneously according to the equation: 



g = Hg + Hg(CH 3 ) 2 . 



Not only do the ions of the organic bases, therefore, resemble the metallic 

 elements, but the free basic groups themselves, when they possess suffi- 

 cient stability to admit of their being isolated, exhibit metallic properties. 

 The metallic state of a substance is not one characteristic merely of ele- 

 ments which themselves are metallic in the elementary condition, but 

 includes likewise various groups of elements whose constitution is such 

 that they carry a negative electron which is relatively loosely attached to 

 the group. 



8. Complex Anions. Our knowledge of the structure of anion com- 

 plexes is comparatively limited. No data are so far available which 

 definitely establish that the anions in water are hydrated. It is true, 

 that, from the conductance values of the anions and the hydration values 

 of the cations, it may be inferred that the anions are likewise hydrated, 

 but the hydration of the anions has not been experimentally verified. 



"Coehn, Ztschr. f. Anorg. Chem. 25, 430 (1900). 

 18 McCoy and Moore, J. Am. Chem. Soc. S3, 273 (1911). 



"Palmaer, Ztschr. g. Electroch. 8, 729 (1902) ; Kraus, V. Am. Chem. Soc. S5, 1732 

 (1913) . 



Kraus, Joe. cit. 



