Chemical Properties
crystalline powder
Physical properties
Red monoclinic crystals or brownish-red powder; density 5.625 g/cm
3; insoluble in water; soluble in nitric acid, ammonia and solutions of alkali cyanides and chromates.
Uses
Catalyst for formation of aldol from alcohol; formed at end point of Mohr titration of halides.
Preparation
Silver chromate is prepared by slowly adding a solution of potassium chromate to a solution of silver nitrate:
2Ag+ (aq) + Cr
4O
2- (aq) → Ag
2CrO
4 (s)
The precipitate is washed with hot water.
Purification Methods
Wash the red-brown powder with H2O, dry it in a vacuum, then powder well and dry again in a vacuum at 90o/5hours. Its solubility in H2O is 0.0014% at 10o. Store it in the dark. [Cardillo & Shimizu J Org Chem 42 4268 1977.]
