Nickel ammonium lead nitrite

In 140 water samples from the river Saale, sampled from 1986 to 1988 according to the technique described in Section 8.1.1.1, the heavy metals iron and zinc were determined using flame AAS and lead, cadmium, chromium, cobalt, copper, and nickel by AAS with electrothermal atomization in the soluble fraction (particle diameter <0.45 pm). The sampling points, located in Thuringia (Germany), are illustrated in Fig. 8-7. The method of standard addition, with three additions, was used to minimize matrix effects. The components ammonium, chloride, magnesium, nitrate, nitrite, phosphate, oxygen,... 

The formation of (II) provides a quite selective spot test for palladium. Gold must be removed prior to the test because it will cause the development of a deep ruby red in the spot plate test and a diffused violet spot on the paper, apparently due to the reduction of the gold ions to the colloidal metal. Interference may also arise from 0s04 , Os+, Ru+, and RuCle ions because they have distinct self-colors. Mercurous ion causes partial interference by the reduction of part of the palladium to the elementary state, but a positive response can still be seen. It is possible to detect I part of palladium in the presence of 200 parts of platinum or 100 parts of rhodium. Less favorable ratios should be avoided because of the color of these salts. No interference is caused by mercuric and iridic chloride, but free ammonia, ammonium ions, stannous, cyanide, thiocyanate, fluoride, oxalate, and tetraborate ions do interfere. Lead, silver, ferrous, ferric, stannic, cobaltous, nickel, cupric, nitrite, sulfate, chloride, and bromide ions do not interfere. 

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