CHLORO-BROMIDE EMULSION.—An emulsion containing both a chloride and a bromide.
CHLOROFORrl (Formula, CH ; molecular weight, 119.52 ; synonyms, methenyl chloride, formyl is prepared by the distillation of a mixture containing bleaching powder, slacked lime, water, and alcohol. The alcohol and water are added together and warmed in a still fitted with a condenser. The bleaching powder is then added and temperature increased until chloroform begins to come over, after which the distillation becomes complete by the heat evolved in the reaction. Chloroform is also largely prepared from rectified spirit and methylated spirit. The purest quality is that prepared by the action of alkalies on previously purified chloral.
Chloroform is a liquid having a sweet pleasant taste and an agreeable ethereal odor. It dissolves in all proportions in alcohol and ether and slightly in water. It burns with a green
Chloroform is used in many photographic operations, chiefly on account of its properties as a solvent for alkaloids, as well as for iodine, bromine, camphor, resins, indiarubber, sulphur, fats, and many other organic bodies.
It is sometimes adulterated with alcohol, wood spirit, methylated chloroform, and sulphuric acid. These impurities may be detected by addition of ferrous di-nitro sulphide, prepared by acting on ferric chloride with a mixture of potassium nitrate and ammonium sulphide. If it acquires a green color, the impurities already mentioned are present Chloroform should be kept in a dark place, for if exposed to air and sunlight it resolves itself into hydrochloric acid, chlorine and other products, unless it be entirely free from nitryl compounds.