Definition. - A liquid containing not less than 99 per cent. by weight of absolute acetone. (U. S. P.)

Acetone is chemically dimethyl-ketone (CH3COCH3). It is present to a considerable extent in crude wood alcohol.

Description and Properties. - It is a clear, colorless, mobile, neutral liquid, inflammable, and having an ethereal odor and taste. Specific gravity, 0.790 (250 C.); boiling-point, 56.50 C. It is miscible with water and alcohol in all proportions, and is an excellent solvent for fats, resins, rubber, etc. Iodoform is formed when acetone is slightly warmed with an alkali and iodine (basis of method for determining acetone in diabetic urine). Acetone is used widely in the manufacture of chloroform, iodoform, and sulphonal. A number of oleoresins (aspidium, capsicum, ginger, lupulin, and pepper) formerly prepared (U. S. P. 1890) with ether are now prepared with acetone.

Physiological Action. - Acetone resembles ethyl alcohol in its action. It is more potent than ordinary alcohol, as a rule. This may be due to delayed elimination, as is the case in wood-alcohol poisoning, which latter, volume for volume, is less poisonous than ethyl alcohol, but being eliminated more slowly becomes practically more poisonous.

Related Compounds. - When a phenyl radical (C6H5) takes the place of one of the methyl groups in acetone, the resulting compounds is phenyl-methyl-ketone (C6H5COCH3), also known as ace-tophenone. This has been used as a hypnotic under the name of Hypnone. It is a liquid above 20.5 C. Malarine is a condensation product of acetophenone and paraphenetidin. It is usually employed in the form of the citrate.

Salacetolum is a salicylic acid ester of acetol, which is an alcohol (CH3COCH1OH) derived from acetone; proposed as an antirheumatic.

Aceto-acetic acid, also called diacetic acid (CH3COCH1COOH), or acetone in which a hydrogen atom has been replaced by (COOH), is found in the urine of many patients suffering from diabetes mel-litus. This acetone is thought to be a decomposition product of diacetic acid.