1 J-T.] 



METHANE 



25 



subsequent reduction as above under D. 

 According to Berthelot (see above under 

 I) methane is among the gases produced 

 by the reduction of acetone by heating 

 to a high temperature with strong 

 aqueous hydriodic acid. 



Acetone also gives bromoform by 

 electrolysis in presence of potassium 

 bromide and carbonate (Cough lin, Am. 

 Ch. Journ. 27, 63 : compare Elbs and 

 Herz, Zeit. Elektroch. 4, 113). 



[K.] Butyric aldehyde [94] gives 

 iodoform by the action of iodine and 

 alkali (Lieben, as above under E). 



[L.] From carbon disulphide [160] 

 by passing the vapour mixed with 

 sulphuretted hydrogen over heated 

 copper (Berthelot, Comp. Rend. 43, 236 ; 

 Ann. Chim. [3] 63, 69). Or from 

 carbon disulphide by heating with phos- 

 phonium iodide to I2O-14O (Jahn, 

 Ber. 13, 127). 



Or carbon disulphide on chlorination 

 in the presence of iron and iodine and 

 subsequent treatment of the product 

 with bleaching powder gives carbon 

 tetrachloride (Serra, Gazz. 29, 353). Or 

 carbon disulphide can be converted into 

 the tetrachloride by chlorination (Kolbe, 

 Ann. 45,41 ; 64, 146; Hofmann, Ann. 

 115, 264; Klason, Ber. 20, 2376; 

 Mouneyrat, Bull. Soc. [3] 19, 262 : 

 for references to technical processes see 

 Conroy, Journ. Soc. Ch. Ind. 21, 309 ; 

 Urbain, Eng. Pat. 13733 ^ I 9 I '> 

 Journ. Soc. Ch. Ind. 21, 926). Carbon 

 tetrachloride can be reduced to methane 

 in the same way as chloroform (Berthe- 

 lot, Jahresber. 1867, 267). 



[M.] Phenol [60] gives methane 

 among the products of pyrogenic de- 

 composition (Miiller, Journ. pr. Ch. 58, 

 I ) . Or phenol by the action of potassium 

 chlorate and hydrochloric acid gives tri- 

 chlor-aa-glyceric acid, which is decom- 

 posed by cold alkaline solutions into 

 oxalic acid and chloroform (Schreder, 

 Ann. 177, 282). 



[N.] From cresol [61; 62; 63] by 

 pyrogenic decomposition (Miiller, as 

 above under M). 



[O.] Fromformic a^[Vol. II], being 

 among the products of the dry distilla- 

 tion of the barium salt (Berthelot, 

 Jahresber. 1857, 426) and of the action 



of heated zinc dust on the vapour of the 

 acid (Jahn, Ber. 13, 2109). 



Or methyl formate on extreme chlo- 

 rination gives perchlormethyl formate 

 (Hentschel, Journ. pr. Ch. [2] 36, 100 ; 

 214; 305), which is decomposed by 

 aluminium chloride with the formation 

 of carbon tetrachloride (Kid. 308). Sub- 

 sequent steps as above under L. 



[P.] From acetic acid [Vol. II] by 

 heating acetates with barium oxide, with 

 potash-lime or soda-lime (Dumas, Ann. 

 Chim. [2] 73, 92; Ann. 33, 181 ; Von 

 Schlegel, Ann. 226, 140; Schorlemmer, 

 Ch. News, 29, 7 : compare Ladenburg 

 and Kriigel, Ber. 32, 1820). Also from 

 acetic acid by photochemical decom- 

 position in the presence of uranium 

 salts (Fay, Am. Ch. Journ. 18, 287). 

 Also by the electrolysis of fused potas- 

 sium acetate (Lassar-Cohn, Ann. 251, 



. 



Or indirectly from acetic acid through 

 the trichloro-acid by chlorination (Du- 

 mas, Ann. 32, 101). The trichloro-acid 

 gives chloroform on heating with 

 aqueous alkali (Ibid. 113; Ann. Chim. 

 [2] 56, 115). 



[Q.] Glycollic acid [Vol. II] gives 

 methane on distillation with lime (Han- 

 riot, Bull. Soc. [2] 45, 80; Comp. Rend. 

 101, 1156). 



[R.] Lactic acid [Vol. II] gives iodo- 

 form by the action of iodine and alkali 

 (Lieben, as above under E). Subsequent 

 reduction as before. Or lactic acid gives 

 chloroform on treatment with bleaching 

 powder (Eberhard, Journ. Ch. Soc. 80, 

 I, Abst. 357). Subsequent reduction as 

 above under D. 



[S.] From malonic acid [Vol. II], 

 ethylene being among the products of 

 the electrolysis of the acid potassium 

 salt (Petersen, Ch. Centr. 1897, 2, 

 519). Ethylene gives methane as above 

 under D. 



[T.] From succinic acid [Vol. II], 

 methane being among the products of 

 electrolysis of an alcoholic solution in 

 presence of sodium hydroxide (Clark and 

 Smith, Journ. Am. Ch. Soc. 21, 967). 



Or indirectly through ethylene by 

 the electrolysis of a strong solution of 

 the sodium salt (Kekule, Ann. 131, 79 ; 

 Clark and Smith, loc. cit.\ also from 



