Benzoyl-m-nitroacetanilide as a Reagent for the Gravimetric Determination of Nickel (II) and Cobalt (II)

Department of Chemistry, The University of Burdwan, Burdwan, West Bengal Manuscript received 15 February 1975; accepted 5 April 1975 Nickel(II) and Cobalt(II) have been precipitated with benzoyl-m-nitroacetanilide as Ni (C15H11O4N2)2 and Co(C15H11O4N2)2 2H2O at \(p\)H 6.5--7.0 and 5.4--7.0 respectively. The complexes were dried at 120° for weighing. The presence of Ag+ and Tl+ do not effect the estimation. As magnesium-EDTA, I', Fi', citric acid and ascorbic acid do not interfere, using a suitable masking agent from this list separation of the above two metal ions from Cd2+, Cu2+, Hg2+, Pb2+, Bi3+, Cr3+, Al3+, Fe3+, Mn2+, Zn2+, Zr4+, VO2+, WO42- or MoO42- is possible. Cobalt has also been separated from nickel by precipitating the former with benzoyl-m-nitroacetanilide at \(p\)H 8.5 in the presence of thiocyanate. Nickel has been determined with the same reagent after removing thiocyanate. The nickel content of some samples of steel and nickel-ore has also been estimated. The standard deviation has been calculated as ±0.17% and ±0.07% in 40 determinations of nickel and cobalt respectively