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methanoic acid(mĕth'ənō`ĭk), HCO2H, a colorless, corrosive liquid with a sharp odor; it boils at 100.7°C; and solidifies at 8.4°C;. It has the lowest molecular weight and is the simplest of the carboxylic acids. Functionally, it is both an acid and an aldehyde. Like other acids, it reacts with most alcohols to form esters and decomposes when heated; like other aldehydes, it is easily oxidized. Formic acid occurs in the bodies of red ants and in the stingers of bees. It can be made by the oxidation of formaldehydeformaldehyde
, HCHO, the simplest aldehyde. It melts at −92°C;, boils at −21°C;, and is soluble in water, alcohol, and ether; at STP, it is a flammable, poisonous, colorless gas with a suffocating odor.
..... Click the link for more information. ; it is prepared commercially by heating carbon monoxide and sodium hydroxide to form sodium formate which, when carefully treated with sulfuric acid, yields formic acid. Formic acid is used industrially in textile dyeing, in leather tanning, and in coagulating latex rubber.
the simplest monobasic carboxylic acid, HCOOH. It is a colorless, highly mobile liquid with a sharp odor. Melting point, 8.25°C; boiling point, 100.7°C; density, 1.2126 g/cm (20°C). Formic acid is miscible in all proportions with water, alcohol, and ether; it forms an azeotropic mixture with water (77.4 percent formic acid; boiling point, 107.2°C). Formic acid causes burns upon contact with the skin.
Formic acid is the strongest fatty acid. In addition to properties typical of carboxylic acids (for example, the formation of salts and esters, called formates), it has reducing properties characteristic of aldehydes. For example, upon heating with an ammonia solution of silver oxide, it forms a “silver mirror.” Formic acid is found in fir needles, nettles, fruits, and the caustic secretions of bees and ants (it was discovered in the caustic secretions of ants as early as the 17th century; hence its name, derived from the Latin formica, meaning “ant”).
In industry, formic acid is produced mainly from solid sodium hydroxide and carbon monoxide (6–8 atmospheres at 120°-150°C). The resulting sodium formate, HCOONa, is decomposed by sulfuric acid.
Formic acid is used in mordant dyeing; for the decalcification of skins in their preparation for tanning; in the production of a number of catalysts (for example, nickel-containing catalysts); for the preparation of esters, formamide, and dimethylformamide; and in the canning of juices.