ELECTROLYTIC SYNTHESIS OF DIBASIC ACIDS. 223 



When the electric current was passed through the cold solution, it rapidly diminished 

 in intensity, and in a few moments ceased to flow altogether. This we found to be due 

 to the fact that the product of electrolysis is solid at the ordinary temperature. Heating 

 to 50° restored the current. On completion of the electrolysis a colourless oil was seen 

 to float to the surface of the liquid, and this oil on cooling solidified to a white crystalline 

 mass, which was washed several times with water, dried on porous tile, and analysed. 



T628 gr. substance gave "4254 gr. C0 2 and -1687 gr. H 2 . 



Found. Calculated for C 2 2H 42 4 . 



C . . . 71-26 per cent. 71*35 per cent. 



H 11-51 „ 11-35 



The substance thus possessed the composition of the diethyl ether of an acid 

 C 1G H 32 (COOH) 2 . It is fairly soluble in ether and cold alcohol, much more so in hot 

 alcohol, in water quite insoluble. It melts at 43°. When heated it has a somewhat 

 unpleasant smell, and begins to decompose about 200°. To saponify it, it must be 

 treated like the diethyl ether of dicarbododecanic acid. 



The potassium salt is somewhat soluble in alcohol, and easily soluble in hot water. 

 It may be best crystallised out of dilute potash solution, when it separates in the form of 

 very fine needles, which, on being sucked dry by the filter-pump, agglomerate into a felt- 

 like mass with a beautiful pearly lustre. Even very dilute aqueous solutions of this salt 

 are extremely soapy. 



The acid precipitated from such a solution is gelatinous, but on recrystallisation from 

 alcohol it forms delicate transparent plates. It is not very soluble in ether, and practi- 

 cally insoluble in water. Its melting-point is 118°. 



Analysis — 



1043 gr. substance gave 2625 gr. C0 2 and -1070 gr. H 2 . 



Found. Calculated for C 18 H 34 4 . 



C 6864 per cent. 68 - 79 per cent. 



H 1102 „ 1083 



The alkaline salts are soluble in water, and their solutions are precipitated by neutral 

 salts of the other metals. The precipitates are voluminous and mostly somewhat 

 gelatinous. The lithium salt is slightly soluble ; the rest are insoluble. The following 

 salts are coloured : — copper salt, bluish green ; ferric salt, brownish yellow ; ferrous salt, 

 brown ; chromium and nickel salts, greenish ; cobalt salt, pink. 



Potassium salt.— (I.) -3565 gr. gave 1253 gr. K 2 C0 3 ; (II.) -3592 gr. gave -1618 gr. 

 K 2 S0 4 . Calculated for K 2 C 18 H 32 4 , 20*00 per cent.; found (1.) 19*87 per cent.; (II.) 

 20-18 per cent. K. 



Barium salt— -3490 gr. gave 1814 gr. BaS0 4 . Calculated for BaC 18 H 32 4 , 30'5 

 per cent. ; found 30 '6 per cent. Ba. 



Magnesium salt.— -4762 gr. gave "0570 gr. MgO. Calculated for MgC 18 H 32 4 , 7'26 

 per cent. ; found 7 '22 per cent. Mg. 



VOL. XXXVI. PART I. (NO. 7). 2 L 



