1. Alkali-thiocyanate is a sensitive reagent for the detection of cobalt in presence of 40 to 50% acetone. Ferric iron can be made harmless by addition of an excess of fluoride. A procedure has been developed for the application of the reaction as a micro-and macro test for cobalt. Cupric copper gives a sensitive reaction and must be removed. The thiocyanate is preferable to cyanate as a reagent.

2. A procedure has been described for the micro detection of thiocyanate by evaporating a drop of the solution to be tested with a small drop of cobalt sulfate and moistening the residue with acetone. The formation of a distinctly green solution indicates the presence of thiocyanate. Nitrite interferes.

Authors and Affiliations

1. Contribution from the School of Chemistry University of Minnesota, USA

   I. M. Kolthoff

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