USP(191)鑒別實(shí)驗(yàn)譯文

1、USP32附錄191 一般鑒別試驗(yàn)： Under this heading are placed tests that are frequently referred to in the Pharmacopeia for the identification of official articles. NOTE The tests are not intended to be applicable to mixtures of substances unless so specified. 此處列舉的檢查項(xiàng)目都是頻繁應(yīng)用于藥典鑒別項(xiàng)下的內(nèi)容：（注：除另有規(guī)定外，不適用于混合物） Acetate

2、 When acetic acid or an acetate is warmed with sulfuric acid and alcohol, ethyl acetate, recognizable by its characteristic odor, is evolved. With neutral solutions of acetates, ferric chloride TS produces a deep red color that is destroyed by the addition of mineral acids. 醋酸鹽：1、當(dāng)醋酸或者醋酸鹽與硫酸、乙醇和乙酸乙酯

3、一起加熱時(shí)，應(yīng)逐漸產(chǎn)生醋酸的特征氣味。2、醋 酸鹽的中性溶液中加入三氯化鐵試液，溶液應(yīng)顯深紅色，加入無機(jī)酸后顏色應(yīng)被破壞。 Aluminum With 6 N ammonium hydroxide, solutions of aluminum salts yield a gelatinous, white precipitate that is insoluble in an excess of 6 N ammonium hydroxide. 1 N sodium hydroxide or sodium sulfide TS produces the same precipitate, whi

4、ch dissolves in an excess of either of these reagents. 鋁：1、鋁鹽溶液中加入 6N的氨水，應(yīng)產(chǎn)生白色膠狀沉淀，溶液不能溶解于過量的6N的氨水中。2、鋁 鹽溶液加入1N的氫氧化鈉或硫化鈉試液，應(yīng)產(chǎn)生白色膠狀沉淀，當(dāng)上述試液過量時(shí)，沉淀應(yīng)溶解。 Ammonium Ammonium salts are decomposed by the addition of an excess of 1 N sodium hydroxide, with the evolution of ammonia, recognizable by its odor an

5、d by its alkaline effect upon moistened red litmus paper exposed to the vapor. Warming the solution accelerates the decomposition. 銨：銨鹽溶液加入過量的1N的氫氧化鈉溶液，銨鹽應(yīng)分解發(fā)出刺激的氨臭，并使?jié)駶櫟募t色石蕊試紙變 藍(lán)，該反應(yīng)加熱可加速銨鹽的分解。 Antimony With hydrogen sulfide, solutions of antimony （III） compounds, strongly acidified with hydrochlor

6、ic acid, yield an orange precipitate of antimony sulfide that is insoluble in 6 N ammonium hydroxide, but is soluble in ammonium sulfide TS . 銻：三價(jià)銻溶液加入硫化氫鹽酸溶液，應(yīng)產(chǎn)生橘紅色硫化銻沉淀，沉淀不溶于6N的氨水，可溶于硫化銨 試液。 Barium Solutions of barium salts yield a white precipitate with 2 N sulfuric acid. This precipitate is inso

7、luble in hydrochloric acid and in nitric acid. Barium salts impart a yellowish-green color to a nonluminous flame that appears blue when viewed through green glass. 鋇：1、鋇鹽溶液與2N的硫酸反應(yīng)，應(yīng)產(chǎn)生白色溶液。沉淀不溶于鹽酸和硝酸。2、鋇鹽于無光焰中發(fā)出 淡黃綠光，透過綠色玻璃觀察應(yīng)為藍(lán)色。 Benzoate In neutral solutions, benzoates yield a salmon-colored prec

8、ipitate withferric chloride TS . In moderately concentrated solutions, benzoates yield a precipitate of benzoic acid upon acidification with 2 N sulfuric acid. This precipitate is readily soluble in ethyl ether. 苯甲酸鹽：1、苯甲酸鹽的中性溶液與三氯化鐵試液反應(yīng)應(yīng)產(chǎn)生橘紅色沉淀。2、苯甲酸鹽的濃溶液被2N 的硫酸酸化后應(yīng)產(chǎn)生苯甲酸沉淀，沉淀易溶于乙醚。 Bicarbonate See

9、Carbonate . 碳酸氫鹽：參照碳酸鹽 Bismuth When dissolved in a slight excess of nitric acid or hydrochloric acid, bismuth salts yield a white precipitate upon dilution with water. This precipitate is colored brown by hydrogen sulfide, and the resulting compound dissolves in a warm mixture of equal parts of nitr

10、ic acid and water. 鉍：鉍鹽的水稀釋液加入稍過量的硝酸或者鹽酸，應(yīng)產(chǎn)生白色沉淀。沉淀加入硫化氫后變?yōu)樽厣a(chǎn)物溶 于溫?zé)岬南跛崛芤海ㄏ跛幔核?1:1 ）。 Bisulfite See Sulfite . 亞硫酸氫鹽：參照硫酸鹽。 Borate To 1 mL of a borate solution, acidified with hydrochloric acid to litmus, add 3 or 4 drops ofiodine TS and 3 or 4 drops of polyvinyl alcohol solution (1 in 50): an inten

11、se blue color is produced. When a borate is treated with sulfuric acid, methanol is added, and the mixture is ignited, it burns with a green-bordered flame. 硼酸鹽：1、1ml硼酸鹽溶液用鹽酸酸化至對(duì)石蕊試紙顯酸性，加入3-4滴碘試液和3-4滴聚乙烯醇溶液 (1:50 )，溶液應(yīng)顯深藍(lán)色。2、硼酸鹽溶于硫酸，加入甲醇后點(diǎn)燃，火焰邊緣應(yīng)為綠色。 Bromide Solutions of bromides, upon the addition

12、of chlorine TS, dropwise, liberate bromine, which is dissolved by shaking with chloroform, coloring the chloroform red to reddish brown. Silver nitrate TS produces in solutions of bromides a yellowish-white precipitate that is insoluble in nitric acid and is slightly soluble in 6 N ammonium hydroxid

13、e. 溴化物：1、溴化物溶液逐滴加入氯試液，游離岀溴，用氯仿萃取，氯仿層應(yīng)為紅棕色。2、溴化物溶液中 加入硝酸銀試液，應(yīng)產(chǎn)生淺黃色沉淀，沉淀不溶于硝酸，易溶于6N的氨水。 Calcium Solutions of calcium salts form insoluble oxalates when treated as follows. To a solution of the calcium salt (1 in 20) add 2 drops of methyl red TS , and neutralize with 6 N ammonium hydroxide. Add 3 N hyd

14、rochloric acid, dropwise, until the solution is acid to the indicator. Upon the addition ofammonium oxalate TS , a white precipitate is formed. This precipitate is insoluble in 6 N acetic acid but dissolves in hydrochloric acid. Calcium salts moistened with hydrochloric acid impart a transient yello

15、wish-red color to a nonluminous flame. 鈣：1、鈣鹽溶液(1:20 )中加入2滴甲基紅試液，用6N的氨水中和，緩緩滴加 3N的鹽酸使其恰成酸性， 加入草酸銨試液，應(yīng)生成白色沉淀。沉淀不溶于6N乙酸，溶于鹽酸。2、用鹽酸潤濕的鈣鹽于無光焰中應(yīng) 呈磚紅色。 Carbonate Carbonates and bicarbonates effervesce with acids, evolving a colorless gas that, when passed into calcium hydroxide TS , produces a white preci

16、pitate immediately. A cold solution (1 in 20) of a soluble carbonate is colored red by phenolphthalein TS, while a similar solution of a bicarbonate remains unchanged or is only slightly colored. 碳酸鹽：1、碳酸鹽與碳酸氫鹽遇酸，劇烈反應(yīng)，生成的氣體通入氫氧化鈣溶液中，產(chǎn)生白色沉淀。2、碳 酸鹽溶液加入酚酞試液顯紅色，同濃度的碳酸氫鹽也呈現(xiàn)紅色或略淺的紅色。 Chlorate Solutions of

17、 chlorates yield no precipitate with silver nitrate TS . The addition of sulfurous acid to this mixture produces a white precipitate that is insoluble in nitric acid, but is soluble in 6 N ammonium hydroxide. Upon ignition, chlorates yield chlorides, recognizable by appropriate tests. When sulfuric

18、acid is added to a dry chlorate, decrepitation occurs, and a greenish yellow-gas is evolved. Caution Use only a small amount of chlorate for this test, and exercise extreme caution in performing it. 氯酸鹽：1、氯酸鹽溶液加入硝酸銀試液不會(huì)出現(xiàn)沉淀，當(dāng)加入亞硫酸鹽混合后，產(chǎn)生白色沉淀，沉淀不溶 于硝酸，可溶于6N的氨水。2、用適當(dāng)?shù)姆椒勺C明氯酸鹽經(jīng)點(diǎn)燃或加熱應(yīng)產(chǎn)省氯氣。3、向干燥的氯酸 鹽上滴加硫

19、酸，劇烈反應(yīng)，并產(chǎn)生黃綠色氣體。(警告：進(jìn)行此試驗(yàn)應(yīng)使用極小量氯酸鹽，且操作時(shí)要謹(jǐn) 慎小心。) Chloride 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. When testing amine (including alkaloidal) hydrochlorides that do not

20、 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. Centrifuge the mixture witho

21、ut delay, and decant the supernatant layer. Wash the precipitate with three 1-mL portions of nitric acid solution (1 in 100), and discard the washings. Addammonia TS dropwise to this precipitate. It dissolves readily. When a monograph specifies that an article responds to the test for dry chlorides,

22、 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. 氯化物：1、加入硝酸銀試液，可產(chǎn)生白色凝乳狀沉淀，沉淀不溶于硝酸，但可溶于6N的氫氧化銨。2、 如果測試胺類鹽酸鹽（

23、包括生物堿類）不能如上述反應(yīng)，除另有規(guī)定外，準(zhǔn)備供試品溶液2ml （約含2mg 氯離子），加入一滴稀硝酸和0.5ml硝酸銀試液，應(yīng)岀現(xiàn)白色凝乳狀沉淀，立即離心分離，棄去上清液， 沉淀分3次用1ml硝酸溶液（1 -100）洗滌，棄去洗滌液。逐滴滴加氨試液，沉淀即溶解。 3、如標(biāo)準(zhǔn)中 規(guī)定只能用干燥固體氯化物實(shí)驗(yàn)，將供試品與二氧化錳等量混合，用硫酸潤濕，緩緩加熱，應(yīng)產(chǎn)生氯氣， 使?jié)駶櫟牡矸鄣饣浽嚰堊兯{(lán)。 Citrate To 15 mL of pyridine add a few mg of a citrate salt, dissolved or suspended in 1 mL of wa

24、ter, and shake. To this mixture add 5 mL of acetic anhydride, and shake: a light red color is produced. 檸檬酸鹽：取數(shù) mg檸檬酸鹽溶于1ml水中，加入15ml吡啶，振搖使懸浮，再加入5ml醋酐，振搖，溶 液應(yīng)顯淡紅色。 Cobalt Solutions of cobalt salts （1 in 20） in 3 N hydrochloric acid yield a red precipitate when heated on a steam bath with an equal vol

25、ume of a hot, freshly prepared solution of 1-nitroso-2-naphthol （1 in 10） in 9 N acetic acid. Solutions of cobalt salts, when saturated with potassium chloride and treated with potassium nitrite and acetic acid, yield a yellow precipitate. 鉆：1、鉆鹽的3N鹽酸溶液（1:20 ）與等量的新配的熱的1-硝基2-萘酚的9N的醋酸溶液（1:10 ）混合， 于蒸氣浴

26、中，應(yīng)產(chǎn)生紅色沉淀。2、鉆鹽溶液用氯化鉀飽和，經(jīng)亞硝酸鉀和醋酸處理，應(yīng)產(chǎn)生黃色沉淀。 Copper Solutions of cupric compounds, acidified with hydrochloric acid, deposit a red film of metallic copper upon a bright, untarnished surface of metallic iron. An excess of 6 N ammonium hydroxide, added to a solution of a cupric salt, produces first a bl

27、uish precipitate and then a deep blue-colored solution. With potassium ferrocyanide TS , solutions of cupric salts yield a reddish-brown precipitate, insoluble in diluted acids. 銅：1、供試品溶液經(jīng)鹽酸酸化后，放入表面光滑明亮的金屬鐵，在鐵表層應(yīng)形成一層紅色的膜。2、銅鹽 溶液中加入過量的6N的氨水，先產(chǎn)生淡藍(lán)色（青黃色）沉淀，沉淀逐漸變?yōu)樯钏{(lán)色。3、供試品與亞鐵氰 化鉀試液反應(yīng)生成紅褐色沉淀，沉淀不溶于稀酸。 Hyp

28、ophosphite When strongly heated, hypophosphites evolve spontaneously flammable phosphine. Hypophosphites in solution yield a white precipitate with mercuric chloride TS . This precipitate becomes gray when an excess of hypophosphite is present. Solutions of hypophosphites, acidified with sulfuric ac

29、id, and warmed with cupric sulfate TS yield a red precipitate. 次磷酸鹽：1、次磷酸鹽加強(qiáng)熱，產(chǎn)生磷化氫，并能自燃。2、供試品溶液中加入氯化汞試液，產(chǎn)生白色沉 淀，當(dāng)供試品過量時(shí)，沉淀顏色變?yōu)榛疑?、供試品溶液用硫酸酸化后，加入硫酸銅試液，溫?zé)?，產(chǎn)生紅 色沉淀。 Iodide Solutions of iodides, upon the addition of chlorine TS, dropwise, liberate iodine, which colors the solution yellow to red. When

30、the solution is shaken with chloroform, the latter is colored violet. The iodine thus liberated gives a blue color with starch TS . Silver nitrate TS produces, in solutions of iodides, a yellow, curdy precipitate that is insoluble in nitric acid and in 6 N ammonium hydroxide. 碘化物：1、碘化物溶液中逐滴滴加氯試液，碘析岀

31、，溶液顏色從黃色變?yōu)榧t色，添加氯仿振搖提取，氯仿 層顯紫色。2、如上述，析出的含碘溶液加入淀粉試液，溶液顯藍(lán)色。3、碘化物溶液中加入硝酸銀試液， 應(yīng)生成黃色凝乳狀沉淀，沉淀不溶于硝酸和6N的氨水。 Iron Ferrous and ferric compounds in solution yield a black precipitate withammonium sulfide TS . This precipitate is dissolved by cold 3 N hydrochloric acid with the evolution of hydrogen sulfide. 鐵：鐵

32、和亞鐵化合物的溶液中加入硫化銨試液，產(chǎn)生黑色沉淀，沉淀溶于冷的3N的含有硫化氫的鹽酸溶 液。 Ferric Salts Acid solutions of ferric salts yield a dark blue precipitate withpotassium ferrocyanide TS With an excess of 1 N sodium hydroxide, a reddish-brown precipitate is formed. Withammonium thiocyanate TS , solutions of ferric salts produce a deep

33、 red color that is not destroyed by dilute mineral acids. 鐵鹽：1、鐵鹽的酸溶液加入亞鐵氰化鉀溶液，生成深藍(lán)色沉淀，加入過量的1N的氫氧化鈉，沉淀變?yōu)榧t 褐色。2、向鐵鹽溶液中加入硫氰酸銨試液，溶液即顯血紅色，加入稀無機(jī)酸，顏色不改變。 Ferrous Salts Solutions of ferrous salts yield a dark blue precipitate with potassium ferricyanide TS . This precipitate is insoluble in 3 N hydrochlori

34、c acid but is decomposed by 1 N sodium hydroxide. With 1 N sodium hydroxide, solutions of ferrous salts yield a greenish-white precipitate, the color rapidly changing to green and then to brown when shaken. 亞鐵鹽：1、亞鐵鹽溶液加入亞鐵氰化鉀試液，生成深藍(lán)色沉淀，沉淀不溶于3N的鹽酸，但可分解于1N 的氫氧化鈉溶液。2、供試品溶液加入1N的氫氧化鈉，生成淡綠色沉淀，振搖，沉淀隨即變?yōu)榫G色，

35、繼而 變?yōu)樽厣?Lactate When solutions of lactates are acidified with sulfuric acid, potassium permanganate TS is added, and the mixture is heated, acetaldehyde is evolved. This can be detected by allowing the vapor to come into contact with a filter paper that has been moistened with a freshly prepared mi

36、xture of equal volumes of 20% aqueous morpholine and sodium nitroferricyanide TS: a blue color is produced. 乳酸鹽：乳酸鹽溶液經(jīng)硫酸酸化后，加入高錳酸鉀試液，混勻，加熱，產(chǎn)生的氣體通向用混合液（等量20% 嗎啉水溶液與亞硝基鐵氰化鈉試液混合）濕潤的濾紙，應(yīng)顯藍(lán)色。 Lead With 2 N sulfuric acid, solutions of lead salts yield a white precipitate that is insoluble in 3 N hydrochlo

37、ric or 2 N nitric acid, but is soluble in warm 1 N sodium hydroxide and inammonium acetate TS . With potassium chromate TS , solutions of lead salts, free or nearly free from mineral acids, yield a yellow precipitate that is insoluble in 6 N acetic acid but is soluble in 1 N sodium hydroxide. 鉛：1、鉛鹽

38、溶液與2N的硫酸反應(yīng)，生成白色沉淀，沉淀不溶于3N的鹽酸或2N的硝酸，可溶于1N的 溫?zé)岬臍溲趸c和醋酸銨試液。2、鉛鹽溶液與鉻酸鉀試液反應(yīng)（無無機(jī)酸參與），產(chǎn)生黃色沉淀，沉淀不 溶于6N的乙酸，溶于1N的氫氧化鈉。 Lithium With sodium carbonate TS , moderately concentrated solutions of lithium salts, made alkaline with sodium hydroxide, yield a white precipitate on boiling. The precipitate is soluble in

39、ammonium chloride TS . Lithium salts moistened with hydrochloric acid impart an intense crimson color to a nonluminous flame. Solutions of lithium salts are not precipitated by 2 N sulfuric acid or soluble sulfates （distinction from strontium ）. 鋰：1、供試品溶液與碳酸鈉試液反應(yīng)，用氫氧化鈉堿化，煮沸，生成白色沉淀，沉淀溶于氯化銨試液。2、 鋰鹽經(jīng)鹽酸

40、濕潤后于無光焰中呈現(xiàn)深紅色。3、鋰鹽溶液與硫酸或可溶性硫酸鹽混合，不產(chǎn)生沉淀。（區(qū)別 于鍶） Magnesium Solutions of magnesium salts in the presence of ammonium chloride yield no more than a slightly hazy precipitate when neutralized with ammonium carbonate TS , but on the subsequent addition of dibasic sodium phosphate TS , a white, crystalline

41、 precipitate, which is insoluble in 6 N ammonium hydroxide, is formed. 鎂：鎂鹽溶液加入氯化銨，再加入碳酸銨試液，溶液顯輕微的渾濁，加入磷酸氫二鈉試液，產(chǎn)生白色晶形 沉淀，沉淀不溶于6N的氨水。 Manganese With ammonium sulfide TS , solutions of manganous salts yield a salmon-colored precipitate that dissolves in acetic acid. 錳：二價(jià)錳鹽溶液與硫化銨試液反應(yīng)，生成橙紅色沉淀，沉淀溶于醋酸。 Me

42、rcury When applied to bright copper foil, solutions of mercury salts, free from an excess of nitric acid, yield a deposit that upon rubbing, becomes bright and silvery in appearance. With hydrogen sulfide, solutions of mercury compounds yield a black precipitate that is insoluble inammonium sulfide

43、TS and in boiling 2 N nitric acid. 汞：1、不含過量硝酸的汞鹽溶液，涂布于光亮的銅箔，在其表面摩擦生成明亮的銀色沉積物。2、汞化合 物與硫化氫反應(yīng)生成黑色沉淀，沉淀不溶于硫化銨試液和沸騰的2N的硝酸。 Mercuric Salts Solutions of mercuric salts yield a yellow precipitate with 1 N sodium hydroxide. They yield also, in neutral solutions with potassium iodide TS , a scarlet precipitat

44、e that is very soluble in an excess of the reagent. 汞鹽：1、汞鹽溶液與1N的氫氧化鈉反應(yīng)生成黃色沉淀。2、與碘化鉀試液反應(yīng)生成猩紅色沉淀，沉淀溶 于過量的碘化鉀試液。 Mercurous Salts Mercurous compounds are decomposed by 1 N sodium hydroxide, producing a black color. With hydrochloric acid, solutions of mercurous salts yield a white precipitate that is b

45、lackened by 6 N ammonium hydroxide. With potassium iodide TS , a yellow precipitate, that may become green upon standing, is formed. 亞汞鹽：1、亞汞化合物與1N的氫氧化鈉反應(yīng)分解，即顯黑色。2、亞汞鹽與鹽酸反應(yīng)生成白色沉淀，加 入6N的氨水，沉淀變?yōu)楹谏?、供試品與碘化鉀試液反應(yīng)生成黃色沉淀，放置后，沉淀轉(zhuǎn)為綠色。 Nitrate When a solution of a nitrate is mixed with an equal volume of sul

46、furic acid, the mixture is cooled, and a solution of ferrous sulfate is superimposed, a brown color is 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 permanga

47、nate TS ( distinction from nitrites ). 硝酸鹽：1、供試品與等體積硫酸混合，放冷，緩緩加入硫酸亞鐵試液，于兩液層之間顯棕色。2、供試品 與硫酸混合，加入金屬銅，即產(chǎn)生紅棕色氣體。3、供試品溶液與高錳酸鉀溶液混合，紫色不應(yīng)褪去。(區(qū) 別于亞硝酸鹽) 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. 亞硝酸

48、鹽：1、供試品與稀無機(jī)酸或6N的乙酸反應(yīng)，即生紅棕色氣體。2、溶液可使淀粉碘化鉀試紙變藍(lán)。 Oxalate Neutral and alkaline solutions of oxalates yield a white precipitate withcalcium chloride TS . This precipitate is insoluble in 6 N acetic acid but is dissolved by hydrochloric acid. Hot acidified solutions of oxalates decolorize potassium perman

49、ganate TS. 草酸鹽：1、氯化鈣試液與中性或堿性供試品溶液反應(yīng)生成白色沉淀，沉淀不溶于6N的乙酸，可溶于鹽酸。 2、熱的酸化供試品溶液可使高錳酸鉀試液褪色。 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. 高錳酸鹽：供試品溶液加入適量的硫酸，與冷的過氧化氫試液

50、和亞硫酸氫鈉試液反應(yīng)，即褪色；與草酸試 液加熱，溶液顏色也褪去。 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 th

51、e ethyl ether layer. 過氧化物：供試品溶液經(jīng)硫酸酸化后，與重鉻酸鉀試液反應(yīng)，即顯深藍(lán)色，加入等量乙醚振搖，分離，藍(lán) 色轉(zhuǎn)移至乙醚層。 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 b

52、e ignited before performing the test. With silver nitrate TS , neutral solutions of orthophosphates yield a yellow precipitate that is soluble in 2 N nitric acid and in 6 N ammonium hydroxide. With ammonium molybdate TS , acidified solutions of orthophosphates yield a yellow precipitate that is solu

53、ble 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 2 N nitric acid and in 6 N ammonium hydroxide. With ammonium molybdate TS , a yellow precipitate that is soluble in 6 N ammoni

54、um hydroxide is formed. 磷酸鹽：(注：此項(xiàng)鑒別適用于磷酸鹽，如供試品為焦磷酸鹽，除另有規(guī)定外，試驗(yàn)前應(yīng)先燃燒供試品。) 1、供試品溶液與硝酸銀試液反應(yīng)，即生成黃色沉淀，沉淀溶于2N的硝酸和6N的氨水。2、供試品溶液 經(jīng)酸化后于鉬酸銨試液反應(yīng)，應(yīng)生成黃色沉淀，沉淀溶于6N的氨水，沉淀的形成可能會(huì)緩慢。3、焦磷酸 鹽經(jīng)點(diǎn)燃后，除第一項(xiàng)生成白色沉淀外，與上述反應(yīng)一致。 Potassium Potassium compounds impart a violet color to a nonluminous flame, but the presence of small qua

55、ntities 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 commer

56、cially 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

57、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. 鉀：1、含鉀化合物在無光焰中呈現(xiàn)紫色，但是少量的鈉會(huì)干擾此顏色，可采用藍(lán)色的過濾器遮蔽少量

58、鈉造 成的干擾，這樣可以濾掉589nm鈉的發(fā)射光，而404nm鉀的發(fā)射光可以穿過，習(xí)慣上，使用鉆玻璃，而 其他市售的過濾器也是可用的。2、中性的鉀鹽濃溶液(取決于鉀鹽的溶解度)與酒石酸氫鈉試液反應(yīng)，可 生成白色晶體沉淀，沉淀溶解于6N的氨水、堿溶液或碳酸鹽溶液，沉淀形成過程緩慢，可以用玻璃棒攪 拌或摩擦試管壁加速反應(yīng)進(jìn)程，加入少量的冰乙酸或酒精也可加速沉淀。 Salicylate In moderately dilute solutions of salicylates, ferric chloride TS produces a violet color. The addition of a

59、cids to moderately concentrated solutions of salicylates produces a white, crystalline o precipitate of salicylic acid that melts between 158and 161. 水楊酸鹽：1、適當(dāng)稀釋的水楊酸鹽溶液，與三氯化鐵試液反應(yīng)，即顯紫色。2、向適量的水楊酸鹽溶液中 加入酸，即生成水楊酸白色晶體沉淀，沉淀于 158 -161 融化。 Silver With hydrochloric acid, solutions of silver salts yield a whi

60、te, 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.