supply of chromium oxide (iii), molecular wt. 151.99. maxm. limit of impurities-substances soluble in water =0.3 , cl. = 0.01 ,heavy metal = 0.002 , fe= 0.02 , loss on ignition ( 950 degree c ) = 1.0 brand:-merck or loba. or similar , . hsn code:-2819 .