Printed on: Wed Jan 06 2021, 02:24:25 AM Official Status: Currently Official on 06-Jan-2021 DocId: 1_GUID-C7C65F9B-2BE2-4FD9-8A5C-12DDED356410_3_en-US (EST) Printed by: Jinjiang Yang Official Date: Official as of 01-May-2018 Document Type: USP @2021 USPC 1 Sample: 800 mg of Ammonium Alum Ammonium Alum Analysis: Transfer the Sample to a 400-mL beaker, moisten AINH (SO ) · 12H O 453.33 with 1 mL of glacial acetic acid, and add 50 mL of water, 4 4 2 2 50.0 mL of Edetate disodium titrant and 20 mL of acetic AINH4(SO4)2 237.15 acid–ammonium acetate buffer TS. Warm on a steam bath Sulfuric acid, aluminum ammonium salt (2:1:1), until the solution is complete, and boil gently for 5 min. dodecahydrate; Cool, add 50 mL of alcohol and 2 mL of dithizone TS, and Aluminum ammonium sulfate (1:1:2), dodecahydrate titrate the excess edetate disodium with 0.05 M zinc sulfate [7784-26-1]. VS to a bright rose-pink color. Perform a blank Anhydrous [7784-25-0]. determination, and make any necessary correction. Each mL of 0.05 M Edetate disodium titrant is equivalent to DEFINITION 11.86 mg of AlNH (SO ) . Ammonium Alum contains NLT 99.0% and NMT 100.5% of 4 4 2 Acceptance criteria: 99.0%–100.5% on the dried basis ammonium alum [AlNH4(SO4)2], calculated on the dried basis. IMPURITIES · IRON IDENTIFICATION Sample solution: 6.7 mg/mL · A. Analysis: Add 5 drops of potassium ferrocyanide TS to Sample solution: 50 mg/mL 20 mL of the Sample solution. Analysis: Add 1 N sodium hydroxide dropwise to the Sample Acceptance criteria: No blue color is produced solution. immediately. Acceptance criteria: A precipitate is formed, and it dissolves in an excess of the reagent with the evolution of ammonia, SPECIFIC TESTS recognizable by its alkaline effect upon moistened red · LOSS ON DRYING á731ñ litmus paper exposed to the vapor. Sample: 2.0 g · B. IDENTIFICATION TESTSÐGENERAL, Aluminum á191ñ Analysis: Transfer the Sample, in a tared porcelain crucible, Sample solution: 50 mg/mL to a muffle furnace at 200°. Increase the temperature to Acceptance criteria: Meets the requirements 300°, and dry at 300° to a constant weight. Cool in a · C. IDENTIFICATION TESTSÐGENERAL á191ñ, Sulfate desiccator, and weigh. Sample solution: 50 mg/mL Acceptance criteria: 45.0%–48.0% Analysis: Proceed as directed in Identification TestsÐ · LIMIT OF ALKALIES AND ALKALINE EARTHS General, Sulfate á191ñ, except centrifuge the neutral Sample: 1 g solutions of sulfates and use the supernatants for test B. Analysis: Completely precipitate the aluminum from a Acceptance criteria: Meets the requirements boiling solution of the Sample in 100 mL of water by the addition of sufficient 6 N ammonium hydroxide to render ASSAY the solution distinctly alkaline to methyl red TS, and filter. · PROCEDURE Evaporate the filtrate to dryness, and ignite. Edetate disodium titrant: Prepare and standardize as Acceptance criteria: The weight of the residue is NMT 5 mg directed in Reagents, Volumetric Solutions, Edetate Disodium, (0.5%). Twentieth-Molar (0.05 M). Official https://online.uspnf.com/uspnf/document/1_GUID-C7C65F9B-2BE2-4FD9-8A5C-12DDED356410_3_en-US 1/1.