发布时间 : 星期六 文章USP38附录(191)一般鉴别试验更新完毕开始阅读7b380766d5bbfd0a785673a1
produced at the junction of the two liquids. When a nitrate is heated with sulfuric acid and metallic copper, brownish-red fumes are evolved. Nitrates do not decolorize acidified potassium permanganate TS (distinction from nitrites).
硝酸盐：1、供试品与等体积硫酸混合，放冷，缓缓加入硫酸亚铁试液，使成两液层，接界面显棕色。2、供试品与硫酸混合，加入金属铜，加热，即产生红棕色气体。3、供试品溶液与高锰酸钾溶液混合，紫色不应褪去。（区别于亚硝酸盐）
Nitrite— When treated with dilute mineral acids or with 6 N acetic acid, nitrites evolve brownish–red fumes. The solution colors starch-iodide paper blue.
亚硝酸盐：1、供试品与稀无机酸或6N的乙酸反应，即生红棕色气体。2、溶液可使淀粉碘化钾试纸变蓝。
Oxalate— Neutral and alkaline solutions of oxalates yield a white precipitate with calcium chloride TS. This precipitate is insoluble in 6N acetic acid but is dissolved by hydrochloric acid. Hot acidified solutions of oxalates decolorize potassium permanganate TS. 草酸盐：1、氯化钙试液与中性或碱性供试品溶液反应生成白色沉淀，沉淀不溶于6N的乙酸，可溶于盐酸。2、热的酸化供试品溶液可使高锰酸钾试液褪色。
Permanganate— Solutions of permanganates acidified with sulfuric acid are decolorized by hydrogen peroxide TS and by sodium bisulfite TS, in the cold, and by oxalic acid TS, in hot solution.
高锰酸盐：供试品溶液用的硫酸酸化后，与冷的过氧化氢试液和亚硫酸氢钠试液反应，即褪色；与热的草酸试液反应，溶液也褪色。
Peroxide— Solutions of peroxides slightly acidified with sulfuric acid yield a deep blue color upon the addition of potassium dichromate TS. On shaking the mixture with an equal volume of ethyl ether and allowing the liquids to separate, the blue color is found in the ethyl ether layer.
过氧化物：供试品溶液经硫酸轻微酸化后，与重铬酸钾试液反应，即显深蓝色，加入等量乙醚振摇，分离，蓝色转移至乙醚层。
Phosphate— [NOTE—Where the monograph specifies the identification test
for Phosphate, use the tests for orthophosphates, unless the instructions specify the use of the pyrophosphate tests or indicate that the product is to be ignited before performing the test.] With silver nitrate TS, neutral solutions of orthophosphates yield a yellow
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precipitate that is soluble in 2N nitric acid and in 6N ammonium hydroxide.
With ammonium molybdate TS, acidified solutions of orthophosphates yield a yellow precipitate that is soluble in 6 N ammonium hydroxide. This precipitate may be slow to form. With silver nitrate TS, pyrophosphates obtained by ignition yield a white precipitate that is soluble in 2N nitric acid and in 6 N ammonium hydroxide. With ammonium molybdate TS, a yellow precipitate that is soluble in 6 N ammonium hydroxide is formed. 磷酸盐：（注：此项鉴别适用于磷酸盐，如供试品为焦磷酸盐，除另有规定外，试验前应先燃烧供试品。）1、正磷酸盐的中性溶液，加硝酸银试液，即生成黄色沉淀，沉淀溶于2N的硝酸和6N的氨水。供试品溶液经酸化后加钼酸铵试液，缓慢生成黄色沉淀，沉淀溶于6N的氨水。2、焦磷酸盐经点燃后，加硝酸银试液，产生黄色沉淀，沉淀溶于2N的硝酸和6N的氨水。加钼酸铵，产生黄色沉淀，，沉淀溶于6N氨水。
Potassium— Potassium compounds impart a violet color to a nonluminous flame, but the presence of small quantities of sodium masks the color unless the yellow color produced by sodium is screened out by viewing through a blue filter that blocks emission at 589 nm (sodium) but is transparent to emission at 404 nm (potassium). Traditionally, cobalt glass has been used, but other suitable filters are commercially available. In neutral, concentrated or moderately concentrated solutions of potassium salts (depending upon the solubility and the potassium content), sodium bitartrate TS produces a white
crystalline precipitate that is soluble in 6 N ammonium hydroxide and in solutions of alkali hydroxides and carbonates. The formation of the precipitate, which is usually slow, is accelerated by stirring or rubbing the inside of the test tube with a glass rod. The addition of a small amount of glacial acetic acid or alcohol also promotes the precipitation. 钾：1、含钾化合物在无色光焰中显紫色，但是少量的钠存在时会有干扰，可采用蓝色的过滤器避免钠造成的干扰，这样可以滤掉589nm钠的发射光，而404nm钾的发射光可以穿过。习惯上，使用钴玻璃，但其他市售的过滤器也是可用的。2、中性的钾盐浓溶液（取决于钾盐的溶解度和含钾量）与酒石酸氢钠试液反应，可生成白色晶体沉淀，沉淀溶解于6N的氨水和碱溶液、碳酸盐溶液。沉淀形成过程缓慢，可以用玻璃棒搅拌或摩擦试管壁加速反应进程，加入少量的冰醋酸或乙醇也可加速沉淀。
Salicylate— In moderately dilute solutions of salicylates, ferric chloride TS produces a violet color. The addition of acids to moderately concentrated solutions of salicylates
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produces a white, crystalline precipitate of salicylic acid that melts between 158 and 161.
水杨酸盐：1、取适当稀释的水杨酸盐溶液，与三氯化铁试液反应，即显紫色。2、向适量的水杨酸盐浓溶液中加入酸，即生成水杨酸白色晶体沉淀，沉淀于158°-161°融化。 Silver— With hydrochloric acid, solutions of silver salts yield a white, curdy precipitate that is insoluble in nitric acid, but is readily soluble in 6 N ammonium hydroxide. A solution of a silver salt to which 6 N ammonium hydroxide and a small quantity of formaldehyde TS are added deposits, upon warming, a mirror of metallic silver upon the sides of the container. 银：1、取供试品盐溶液加盐酸，即生成白色凝乳状沉淀，沉淀在硝酸中不溶，但易溶于6N的氨水。2、供试品盐溶液加入6N的氨水及少量的甲醛试液，温热，于容器壁出现金属银镜薄层。
Sodium— Unless otherwise specified in an individual monograph, prepare a solution to contain 0.1 g of the sodium compound in 2 mL of water. Add 2 mL of 15% potassium carbonate, and heat to boiling. No precipitate is formed. Add 4 mL of potassium pyroantimonate TS, and heat to boiling. Allow to cool in ice water and, if necessary, rub the inside of the test tube with a glass rod. A dense precipitate is formed. Sodium compounds impart an intense yellow color to a nonluminous flame.
钠：1、除另有规定外，取0.1g钠盐溶解于2ml水中，加入15%的碳酸钾2ml，加热至沸，应不得有沉淀生成；加入焦锑酸钾试液4ml，加热至沸，冰水中冷却，如必要，使用玻璃棒摩擦试管内壁，应有致密的沉淀生成。2、钠盐于无色光焰中应呈现鲜黄色。
Sulfate— With barium chloride TS, solutions of sulfates yield a white precipitate that is insoluble in hydrochloric acid and in nitric acid. With lead acetate TS, neutral solutions of sulfates yield a white precipitate that is soluble in ammonium acetate TS. Hydrochloric acid produces no precipitate when added to solutions of sulfates (distinction from thiosulfates).
硫酸盐：1、供试品溶液加氯化钡试液，即生成白色沉淀，沉淀在硝酸和盐酸中不溶。2、取供试品的中性溶液加醋酸铅试液，即生成白色沉淀，沉淀溶于醋酸铵试液。3、加入盐酸，供试品溶液不出现沉淀。（区别于硫代硫酸盐）
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Sulfite— When treated with 3 N hydrochloric acid, sulfites and bisulfites yield sulfur dioxide, which blackens filter paper moistened with mercurous nitrate TS.
亚硫酸盐：亚硫酸盐或亚硫酸氢盐加入3N的硝酸，即产生二氧化硫气体，可使经硝酸亚汞试液浸湿的滤纸变黑。
Tartrate— Dissolve a few mg of a tartrate salt in 2 drops of sodium metaperiodate solution (1 in 20). Add a drop of 1 N sulfuric acid, and after 5 minutes add a few drops of sulfurous acid followed by a few drops of fuchsin–sulfurous acid TS: a reddish-pink color is produced within 15 minutes.
酒石酸盐：用2滴高碘酸钠溶液（1:20）湿润数mg供试品，滴加1滴硫酸，放置5分钟，滴加数滴亚硫酸，再继续滴加数滴亚硫酸品红试液，15分钟内应呈粉红色。
Thiocyanate— With ferric chloride TS, solutions of thiocyanates yield a red color that is not destroyed by moderately concentrated mineral acids.
硫氰酸盐：供试品溶液中加入三氯化铁试液，即显红色，加入适量的无机酸颜色不褪。 Thiosulfate— With hydrochloric acid, solutions of thiosulfates yield a white precipitate that soon turns yellow, and sulfur dioxide, which blackens filter paper moistened
with mercurous nitrate TS. The addition of ferric chloride TS to solutions of thiosulfates produces a dark violet color that quickly disappears.
硫代硫酸盐：1、供试品溶液与盐酸反应，即生成白色沉淀，随即沉淀变为黄色，同时生成二氧化硫气体，气体可使经硝酸亚汞试液浸湿的滤纸变黑。2、供试品溶液加入三氯化铁试液，呈现瞬间即逝的深紫色。
Zinc— In the presence of sodium acetate, solutions of zinc salts yield a white precipitate with hydrogen sulfide. This precipitate is insoluble in acetic acid, but is dissolved by 3N hydrochloric acid. Ammonium sulfide TS produces a similar precipitate in neutral and in alkaline solutions. With potassium ferrocyanide TS, zinc salts in solution yield a white precipitate that is insoluble in 3N hydrochloric acid.
锌：1、含有醋酸钠的锌盐溶液与硫化氢反应，生成白色沉淀，沉淀不溶于醋酸，可溶于3N的盐酸。2、中性或碱性的供试品与硫化铵试液反应生成白色沉淀。3、供试品溶液与亚铁氰化钾试液反应生成白色沉淀，沉淀不溶于3N的盐酸。
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