12 ORGANIC AGRICULTURAL CHEMISTRY 



H 



CH2CI2 — Di-chlor-methane, H - C - CI 



I 

 CI 



CI 



CHCI3 — Tri-chlor-methane, H - C - CI 



I 

 CI 



CI 

 CCI4 — Tetra-chlor-methane, CI — C — CI 



CI 



In these compounds and similar ones the groups (CH3), (CH2), 

 (CH) or others containing several carbon groups, which will 

 be found running unchanged through a series of related com- 

 pounds, are termed radicals. The radical CH3 is called methyl 

 and CH3CI is known as methyl chloride as well as mono-chlor- 

 methane. 



By reactions which we shall not now discuss there have been 

 produced other mono substitution products of methane in which 

 the hydroxyl, amino, nitro, cyanogen, etc., groups have been 

 substituted for a hydrogen and they are known by analogous 

 names. The relationship between them and methane itself 

 may be grasped by considering them together. 



CH3 - H, Methyl hydride (Methane) 



CH3 — CI, Methyl chloride (Mono-chlor-methane) 



CH3— Br, Methyl bromide (Mono-brom-methane) 



CH3 — I, Methyl iodide (Mono-iodo-methane) 



CH3 — OH, Methyl hydroxide (Mono-hydroxy-methane) 



CH3 — NH2, Methyl amine (Mono-amino-methane) 



CH3 — CN, Methyl cyanide (Mono-cyano-methane) 



The group of substitution products of methane in which one 

 halogen element is substituted for a hydrogen atom is known by 



