SUBSTITUTION PRODUCTS OF THE HYDROCARBONS 19 



water and soluble in alcohol. It is a very important disinfectant 

 and antiseptic used especially in the dressing of wounds. It also 

 is made from alcohol and its formation is a test for the presence 

 of alcohol. (See Exp. VII, 4.) 



Carbon Tetrachloride, or tetra-chlor-methane, is a heavy 

 liquid resembling chloroform in appearance and general char- 

 acter, but is non-anaesthetic. Its chief use is as a solvent for 

 fats and oils. It is non-inflammable and is used as a constituent 

 of non-inflammable cleaning liquids and also of some fire-ex- 

 tinguishing liquids. 



EXPERIMENT STUDY III 



Halogen Substitution Products 



(i) Chloroform, CHCI3, Tri-chlor -methane, (a) Using 2 to 3 c.c. 

 chloroform, test the compound for general properties, e.g. color, 

 odor, inflammability (pour a few drops on a watch glass and apply 

 flame), solubility in water, in alcohol, specific gravity (heavier or 

 lighter than water), etc. (b) Test solvent action on (i) iodine, (2) fats 

 or oils, (3) sulphur. 



(2) Iodoform, CHI3, Tri-iodo-methane. Examine iodoform as to 

 general character and crystal form (microscope or lens). Test for 

 color, odor, and solubility in water and alcohol. 



(3) Carbon Tetrachloride, CCI4, Tetra-chlor-methane. Repeat the 

 chloroform tests with carbon tetrachloride. 



Halogen Ethanes 



Mono-halogen Ethanes. — The halogen ethanes or ethyl haU 

 ides are analogous to the halogen methanes, e.g. : 



CH4, Methane CH3I, Methyl iodide 



C2H6, Ethane C2H5I, Ethyl iodide 



C2H5Br, Ethyl bromide 

 C2H5CI, Ethyl chloride 



These mono-halogen ethanes are all known and are important 

 synthetic reagents. Ethyl chloride and ethyl bromide are also 

 used as anaesthetics. 



