Identification Tests Cobalt

Cobalt(II) ion forms a deep blue solution with an excess of monothiophosphate ion in a solution made slightly alkaline with sodium acetate. This reaction can be used as a qualitative identification test for cobalt(II) ion in the presence of nickel(II) ion.8 Monothiophosphate ion reacts with lead ion in cool solution to form a white precipitate, which turns brown to black when the suspension is heated. 

Identification of an efficient metal chelate for optimum absorption of NO requires knowledge of the thermodynamics and kinetics of the coordination of NO to various metal chelates. Knowledge is also needed of the kinetics and mechanisms of the reaction between nitrosyl metal chelates and absorbed SO2 in solution to calculate the regeneration rate of metal chelates and to control the products of reaction by adjusting the scrubber operating conditions. Not much of this information is available in the literature, although several ferrous and cobalt chelates have been used as additives for testing in bench-scale wet flue gas simultaneous desulfurization and denitrification scrubbers. 

Uranyl salts react with a-nitroso-jS-naphthol to form a yellow precipitate. It is therefore necessary to take precautions in the presence of uranium, especially when testing for small amounts of cobalt. Uranium may be converted into the non-reacting phosphate by treatment with ammonium phosphate. The test is then carried out as in the presence of iron salts. Limit of Identification 0.26 y cobalt in the presence of 1000 times the Limit of Dilution 1 200,000 ) amount of uranium... 

Flame tests are not commonly used to identify transition metals. The presence of a certain transition-metal ion in a solution is sometimes obvious from the solution s color. Some transition-metal ions can be more accurately identified using a procedure called qualitative analysis. Qualitative analysis is the identification of ions by their characteristic reactions. The transition-metal ions most often identified through qualitative analysis include copper, nickel, zinc, chromium, iron cobalt, cadmium, manganese, and tin. Most tests to identify the presence of an ion in a mixture involve causing the ion to precipitate out of solution. Some of the more dramatic precipitation reactions for transition metals are shown. 

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