ESTIMATION OF FORMALDEHYDE BY ROMIJN'S METHOD IN PRESENCE OF AMMONIUM SALTS

In the hypoiodite oxidation method of estimating formaldehyde, ammonium salts interfere. A mixture of 3% mercuric chloride and about 40% potassium iodide has been found to prevent completely this interference. The usual black precipitate, produced by the action of hypoiodite on ammonium salts, does not appear; the solution remains clear and excellent results are obtained for formaldehyde.