SEPARATION
OF HYI'ONITRITE 459 dcscribccl. Observations wcrc made upon an unchnractcrizctl impurity which was prcscnt in very small amounts in tlw prcpnrecl sodium hyponitritc samples. L'autcur cl&-it la prdparntion cl'un Iiyponitritc tlcsotlium, cscmpt ilc cnrbonatc ct la sc_$xwation tic CCt hypunitritc cl'nvcc nitrite, nitrate ct hyclroxylnminc. par chrorilntogrnpliie sur papior. 2USAMhIENI"ASSUNG ES wircl die I)arstctlutl~ cincs carbonat-frcicn Nntriumh~ponitrits sowic tlic papicrchronmtographischc 'Trcnnllng vc,n Gcrnisclwn van Nntriutnllyporlitrlt. Natriuninitrit, Natriuninitrat untl Hytlroxylaniin bcscliriclxri. GRAVIMETRIC DETERMINATION OF COBALT AND NICKEL, AND THEIR SEPARATIONS FROM COPPER WITH N-BENZOYLPHENYLHYDROXYLAMINE s. Ii. SIpu'l-IA AND S. c. Si+O%~~
N-benzoylphenylhydrosylamine was suggested by SHOMI:' as a reagent for the analysis of many metals and has been used for the gravimctric determination of copper, iron, alumininm and titanium 2, and for the colorimctric estimation of vanadiuma. In the present investigation cobalt and nickel are precipitated separately with this reagent from their hot buffered solutions. The metal complexes correspond to the formulae CO(CKIH~~OZ.N)~ and Ni(ClsHloOaN)z, and can be weighed directly. By adjusting the p1.1 of the solutions it is possible to separate either cobalt or nickel from copper and to determine the component metals of any of the mixtures.
SOLUTIONS USED IN THE DETERMINATION OF THE METALS
Metals to be determined
Separate standard solutions of cobalt sulphate, nickel ammonium sulphate and copper sulphate were prepared to contain x.05 mg of cobalt, 1.22 mg of nickel and 1.32 mg of copper respectively per ml.
All the chemicals used were of A.R. quality.
References p. 46a