56 ELECTROLYSIS AND ELECTROS YN THE SIS 



quinone. The cathode fluids employed were solutions 

 of alkalies, alkali carbonates, chromates, permanga- 

 nates, acidulated water, and dilute acids. Both direct 

 and alternating currents were used. On the elec- 

 trolysis of anthraquinone and potassium hydroxide 

 alizarine is formed. 



Nitro-aldehydes and nitro-ketones will be discussed 

 in the chapter on nitro-compounds. 



3. Acids. 



Benzoic Acid. Benzoic acid and its salts were ex- 

 amined by several investigators, first by Matteuci, 1 

 then by Brester, 8 and most thoroughly by Bourgoin. 8 



The result of all these investigations is to show 

 that here no secondary reactions take place, as was 

 observed in the case of the fatty acids, but that the 

 only effect of the current is to produce a separation 

 into hydrogen (or metal) and the acid radical, the 

 latter regenerating the acid at the positive pole. In 

 an alkaline solution it is possible to so increase the 

 oxidation that the benzoic acid is destroyed. The 

 decomposition products which then appear at the 

 anode are carbon dioxide, carbon monoxide, and 

 sometimes acetylene. The odor of bitter almonds is 

 also frequently observed. A thorough investigation 



1 Bull. soc. chim., 10, 209. 



Jahresb. f. Chem., 1866, p. 87. 



8 Bull. soc. chim., 10, 431. 



