nitrate of silver allow the canary-yellow colored precipitate to subside. When a monograph specifies that an article responds to the test for dry chlorides, mix the solid to be tested with an equal weight of manganese dioxide, moisten with sulfuric acid, and gently heat the mixture: chlorine, which is recognizable by the production of a blue color with moistened starch iodide paper, is evolved. By this operation, the nitric acid is easily broken up into its combinations. Add ammonia TS dropwise to this precipitate. That means, there are no precipitates of nitrate compounds. Does nitrate ion form precipitates with cations All nitrate compounds are soluble in water. So when anion vary, color of preciptate also vary. Wash the precipitate with three 1-mL portions of nitric acid solution (1 in 100), and discard the washings. PbI 2 is yellow colour precipitate and PbCl 2 is white precipitate. Centrifuge the mixture without delay, and decant the supernatant layer. When testing amine (including alkaloidal) hydrochlorides that do not respond to the above test, add one drop of diluted nitric acid and 0.5 mL of silver nitrate TS to a solution of the substance being examined containing, unless otherwise directed in the monograph, about 2 mg of chloride ion in 2 mL: a white, curdy precipitate is formed. (1) Solutions of bromides yield a pale yellow precipitate with silver nitrate TS. With silver nitrate TS, solutions of chlorides yield a white, curdy precipitate that is insoluble in nitric acid but is soluble in a slight excess of 6 N ammonium hydroxide.
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