title: Substoichiometric masking-II Determination of traces of cobalt in nickel salts and metallic nickel.
abstract: Cobalt is determined in the presence of large amounts of nickel by masking the latter substoichiometrically by addition of xxx 98% of the theoretically required amount of EDTA. The "free nickel" :cobalt ratio is thereby decreased below the critical value and the cobalt is extracted as the green cobalt(III)-PAN complex into chloroform. Small amounts of nickel-PAN formed are destroyed by a subsequent EDTA-hydrochloric acid treatment. The absorbance of the treated extract is measured at 635 mmu. Copper, zinc, cadmium and iron do not interfere in ratios (to cobalt) of 500:1, 100:1, 100:1 and 10:1, respectively.
authors.affiliation: School of Chemistry, Georgia Institute of Technology, Atlanta, Ga. 30332, U.S.A.
authors.forename: H
authors.initials: H
authors.lastname: Flaschka
authors.forename: J
authors.initials: J
authors.lastname: Garrett