CHEMISTRY 213 



CH 4 , very closely resembles normal butane, 



CH 3 * CH 2 * CH 2 ' CH a ; and again propionic 

 acid, CII 3 • CII 2 • COOII, and heptylic acid, 

 CH 3 CH 2 CII 2 - CH 2 - CIL- Clio- COOII, are 



very much alike. 



Quite different is the case when any other 

 radical accumulates in the molecule. For 

 instance, propyl alcohol, CII 3 *CII 2 *CII 2 ()II, 

 which closely resembles ordinary alcohol, 

 CH 3 *CH 2 OH, is very different in its behavior 

 from glycerine, CH 2 OH CHOH CH 2 OII, 

 and similarly, acetic acid, CII 3 *COOH, differs 

 materially in properties from oxalic acid 

 COOH* COOII. Even more marked are the 

 differences when a radical accumulates upon 

 a single carbon atom. In successive stages 

 of oxidation ethane, CH 3 *CH 3 , yields alcohol, 

 CH 3 CH 2 OH, aldehyde, CH 3 CH(OH) 2 , which 

 by a secondary transformation goes over into 

 the more stable form CH 3 *CHO, and acetic 

 acid, CH 3 *C(OH) 3 , which similarly becomes 

 CH 3 *COOH. These changes correspond to 

 the conversion of ethane, that is monomethvl 

 methane, into dimethyl methane, trimethyl 

 and tetramethyl methane : — 



CH 3 -CII 3 ->CH 3 CH 2 CH 3 -+ 



CH,y H _ rw _> cn 3 \ r /CH 3 



ch 3 A h " Ltl3 ch/ l \ch i . 



