The anhydrous acid combines with hydrochloric, hydrobromic and hydriodic acids to form crystalline addition products, which are decomposed by water with the formation of the corresponding ammonium salt and formic acid.
The orthoand parasemidines can be readily distinguished by their behaviour with different reagents; thus with nitrous acid the ortho-semidines give azimido compounds, whilst the para-semidines give complex diazo derivatives; with formic or acetic acids the ortho-semidines give anhydro compounds of a basic character, the para-semidines give acyl products possessing no basic character.
Busch (Ber., 1905, 38, pp. 856, 4049) has isolated a series of bridged ring compounds which he describes as endo-iminodihydrotriazoles, the triphenyl derivative (annexed formula) being prepared by condensing triphenylaminoguanidine with formic acid.
Sodium amalgam converts it into formic acid; whilst with alcohol it yields the normal carbonic ester.
Equally good comparisons have been obtained for solutions in other solvents such as acetic acid 3.88, formic acid 2.84, benzene 5.30, and nitrobenzene 6.95.
The sharp, broken end penetrates the skin, and into the slight wound thus formed the formic acid contained by the hair is injected.
Hydrolysis of hydrocyanic acid by means of hydrochloric acid yields formic acid.
It oxidizes readily: exposure to air giving acrylic acid, nitric acid giving oxalic acid, bichromate of potash and sulphuric acid giving carbon dioxide and formic acid.
Secondary alcohols result from the reduction of ketones; and from the reaction of zinc alkyls on aldehydes or formic acid esters.
Finally, formic acid is, as.