Explosion Tollens’ reagent

See FULMINATING METALS, SILVER-CONTAINING EXPLOSIVES, TOLLENS REAGENT... 

See also SILVER-CONTAINING EXPLOSIVES, SILVERING SOLUTIONS, TOLLENS REAGENT See Other CATALYTIC IMPURITY INCIDENTS, JV-METAL DERIVATIVES, SILVER COMPOUNDS... 

Textile clothing static charges, 394 Theory without detailed thought, 394 Thermal explosions, 394 Thermal stability of reaction mixtures and systems, 394 Thermite reactions, 395 Thermochemistry and exothermic decomposition, 396 Thiatriazoles, 400 Thionoesters, 401 Thiophenoxides, 401 Thorium furnace residues, 401 Tollens reagent, 401 Toxic hazards, 402 Trialkylaluminiums, 402 Trialkylantimony halides, 403 Trialkylbismuths, 403... 

At the end of the reaction promptly destroy excess Tollens reagent with nitric acid It can form an explosive fulminate on standing. Nitric acid can also be used to remove silver mirrors from the test tubes. 

Destroy used Tollens reagent promptly with nitric acid. It can form explosive fulminates. 

This mixture of ammoniacal silver oxide and sodium hydroxide solution is potentially dangerous, because if kept for a few horns it deposits an explosive precipitate. This danger was described by Tollens in 1882 but is not generally known now. Prepare the reagent just before use, in the tube to be used for the test, and discard... 

Ammoniacal silver nitrate solution (Totten s solution). Aldehydes alone reduce Tollen s reagent and produce a silver mirror on the inside of the test tube. Add 2-3 drops (or 0.05 g) of the compound to 2-3 ml of Tollen s solution contained in a clean test tube (the latter is preferably cleaned with hot nitric acid). If no reaction appears to take place in the cold, warm in a beaker of hot water. (CAUTION After the test, pour the contents of the test tube into the sink and wash the test tube with dilute nitric acid. Any silver fulminate present, which is highly explosive when dry, will thus be destroyed.)... 

Tollen s test The reagent should be freshly prepared by mixing two solutions (A and B). Solution A is a 10% aqueous AgNOs solution and solution B is a 10% aqueous NaOH solution. When the test is required, 1 ml of solution A and 1 ml of solution B are mixed, and the silver oxide thus formed is dissolved by dropwise addition of 10% aqueous NH4OH. To the clear solution, 10 drops of the compound to be tested are added. A silver mirror is indicative of the presence of an aldehyde. The reagent mixture (A + B) is to be prepared immediately prior to use otherwise, explosive silver fulminate will form. The silver mirror is usually deposited on the walls of the test tube either immediately or after a short warming period in a hot water bath. This is to be disposed of immediately with diluted HN03 (detection limit, 50 mg compounds tested, Q to C6). 

Do not store unused Tollens s reagent, because it decomposes on standing and yields silver azide, AgNg, an explosive precipitate. Follow the directions under Wrapping It Up for proper disposal of the solution. 

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