Prepn of yellow-brown anhydr salt: Aynsley,
Campbell, J. Chem. Soc.1958, 1723. The commercial salt usually contains 20-25% water. Review
of toxicology and human exposure: Toxicological
Profile for Nickel (PB2006-100005, 2005) 397 pp.
Derivative
Tetrahydrate.
Properties
Apple-green powder. Poisonous. Insol in water. Slightly sol in dil acids, freely in alkali cyanides,
in ammonia, and in ammonium carbonate.