Brownish green fine crystalline powder, easily soluble in ethanol, methanol, glacial acetic acid and alkali solution, yellow solution in acetic acid, red purple solution in dilute alkali solution and ammonia water, slightly soluble in water, insoluble in ether, benzene, chloroform, carbon tetrachloride and ethyl acetate; Maximum absorption wavelength 579 (371) nm.

As an acid-base indicator, it has two color change ranges, the first color change range is pH 1.2 (red)~2.8 (yellow), and the second color change range is pH 7.4 (yellow)~9.0 (purple red).

Save as:Sealed storage.