Laboratory preparation of methanoic acid

In the laboratory, formic acid can be obtained by heating oxalic acid in anhydrous glycerol and extraction by steam distillation. Another preparation (which must be performed under a fume hood) is the acidhdrolysis of ethyl isonitrile (C₂H₅NC) using HCl solution.

C₂H₅NC + 2 H₂O → C₂H₅NH₂ + HCO₂H

The isonitrile can be obtained by reacting ethyl amine with chloroform (note that the fume hood is required because of the overpoweringly objectionable odor of the isonitrile).