Gravimetric Determination of Manganese(II) with N-Benzoyl- Phenylhydroxylamine

Department of Chemistry, Jadavpur University, Calcutta-32

Manuscript received 22 February 1974; accepted 4 April 1975

N-Benzoyl-phenylhydroxylamine has been used to determine 5.0 to 28.0 mg of manganese(II) gravimetrically. The complex is precipitated quantitatively within the \(p\)H range, 6.3 to 7.8. The interference due to Mg²⁺, As³⁺, Sb³⁺, MoO₄^2-, WO₄^2-, Cu²⁺, Co²⁺, Zn²⁺, Cd²⁺, Hg²⁺, Pd²⁺, UO₂^2- or La³⁺ has been avoided by using tartrate, cyanide, ammonium carbonate or ammonium acetate as the masking agents. The reagent has also been utilised for the separation of Mn²⁺ from Ti⁴⁺, Fe³⁺, Sn²⁺, VO₃^-, Th⁴⁺ and Al³⁺ by adjustment of acidity. The precipitate is weighed as Mn(C₁₃H₁₀,O₂N)₂ after drying at 110°--120°. The accuracy is generally better than 0.3%.