2246. Chromous Formate

Nomenclature

CAS number: 4493-37-2
C2H2CrO4; mol wt 142.03.
C 16.91%, H 1.42%, Cr 36.61%, O 45.06%.
Cr(HCOO)2.

Description and references

Prepd from CrCl2 and Na formate: Lux, Illman, Ber. 91, 2143 (1958); Earnshaw et al., Proc. Chem. Soc. London 1963, 281. Prepn of blue and red anhydrous forms from hydrated formates: Herzog, Kalies, Z. Chem. 5, 273 (1965).

Derivative

Hemihydrate.

Properties

Violet to blue crystals. Sol in water.

Derivative

Monohydrate.

Properties

Red needles. Sol in water to give blue soln.

Derivative

Hemipentahydrate.

Properties

Large, dark-red cubic crystals. Sol in water, alcohol, ether, acetone.

Use

In baths for Cr electroplating; in catalysts for organic reactions.