Nomenclature
CAS number: 13782-01-9
Hexakis(nitrito-
N)cobaltate(3-) tripotassium; potassium hexanitrocobaltate(III); potassium cobaltinitrite; potassium nitrocobaltate(III); cobalt yellow; Fischer's yellow; C.I. Pigment Yellow 40; C.I. 77357.
CoK
3N
6O
12; mol wt 452.26.
Co 13.03%, K 25.94%, N 18.58%, O 42.45%.
K
3Co(NO
2)
6.
Description and references
Incorrectly called “Indian Yellow”. Prepd by addition of KNO2 to a solution of
a Co salt: Salyer, Sweet, Anal. Chem. 32, 548 (1962).
Properties
Sesquihydrate, yellow, octahedral, cubic crystals.
Very slightly sol in water, dil acetic acid. Practically insol in
alcohol; dec by mineral acids.Use
As an oil- and water-color pigment; in painting
on glass and porcelain; in coloring rubber; in separation of Co from
Ni; in Co analysis.