5882. Mercuric Oxide, Red

Nomenclature

CAS number: 21908-53-2
Mercury oxide (HgO); red precipitate.
HgO; mol wt 216.59.
Hg 92.61%, O 7.39%.

Description and references

Contains 99-99.5% HgO.

Properties

Bright red or orange-red, heavy, odorless, crystalline powder or scales; orthorhombic structure; yellow when finely powdered. Poisonous. Dec on exposure to light into mercury and oxygen; at 400° becomes almost black, but red again on cooling; at 500° dec into mercury and oxygen. d 11.14. Practically insol in water. Sol in dil HCl or HNO3 or in solns of alkali cyanides or iodides, slowly in solns of alkali bromides; insol in alcohol. Protect from light.

Use

In marine bottom paints, diluting pigments for painting on porcelain, with graphite as depolarizer in dry batteries. In Kjeldahl nitrogen determination; and as reagent for citric acid, thiophene, glucose, aldehyde, urea, acetone. As reagent and catalyst in organic reactions: J. S. Pizey, Synthetic Reagents vol. 1 (John Wiley, New York, 1974) pp 295-319.

Therapeutic Category

Antiseptic (topical).

Therapeutic Category (Veterinary)

Has been used as a topical antiseptic.