2634. Cupric Chromate(VI)

Nomenclature

CAS number: 13548-42-0
Neutral cupric chromate.
CrCuO4; mol wt 179.54.
Cr 28.96%, Cu 35.39%, O 35.65%.
CuCrO4.

Description and references

Prepn from CuCO3, Na2CrO4 and CrO3: Briggs, J. Chem. Soc. 1929, 242; from CuO and CrO3: Campbell, Lemaire, Can. J. Res. 25B, 243 (1947); from Cu(OH)2 and K2Cr2O7: Winter et al., in Kirk-Othmer Encyclopedia of Chemical Technology vol. 6 (Interscience, New York, 2nd ed., 1965) p 270.

Properties

Reddish-brown crystals. Gradually dec to CuCr2O4 above 400°. Practically insol in water; sol in acids.

Derivative

Basic cupric chromates.

Properties

Several cupric chromate-cupric hydroxide compounds are known. CuCrO4.Cu(OH)2 forms yellow, copper-red or chocolate-brown to lilac crystals; CuCrO4.2Cu(OH)2, a light brown powder; 2CuCrO4.3Cu(OH)2, yellow to yellowish-brown crystals. Prepn: Campbell, Lemaire, loc. cit.; Winter et al., loc. cit. All are practically insol in water.

Use

In fungicides, seed protectants, and wood preservatives; as mordant in dyeing textiles; in protecting textiles against insects and microorganisms.