AlCl3·6H2O
241.43
Aluminum chloride,hexahydrate.
Aluminum chloride hexahydrate
[7784-13-6].
Anhydrous
133.34
[7446-70-0].
Packaging and storage—
Preserve in tight containers.
Identification—
Asolution (1in 10)responds to the tests for Aluminum á191ñand for Chloride á191ñ.
Sulfate—
The addition of 0.2mLof barium chloride TSto 10mLof a solution (1in 100)produces no turbidity within 1minute.
Limit of alkalies and alkaline earths—
To a boiling solution of 1.0g in 150mLof water add a few drops of methyl red TS,then add 6Nammonium hydroxide until the color of the solution just changes to a distinct yellow.Add hot water to restore the volume to 150mL,and filter while hot.Evaporate 75mLof the filtrate to dryness,and ignite to constant weight:the weight of the residue does not exceed 2.5mg (0.5%).
Iron á241ñ—
Dissolve 1.0g in 45mLof water,and add 2mLof hydrochloric acid:the limit is 0.001%.
Assay—
Edetate disodium titrant—
Prepare and standardize as directed in the
Assayunder
Ammonium Alum.
Procedure—
Transfer to a 250-mLvolumetric flask about 5g of Aluminum Chloride,accurately weighed,dissolve in and dilute with water to volume,and mix.Transfer 10.0mLof the solution to a 250-mLbeaker,and add,in the order named and with continuous stirring,25.0mLof Edetate disodium titrant,and 20mLof acetic acid-ammonium acetate buffer TS,and boil gently for 5minutes.Cool,and add 50mLof alcohol and 2mLof dithizone TS.Titrate with 0.05Mzinc sulfate VSto a bright rose-pink color.Perform a blank determination,substituting 10mLof water for the assay preparation,and make any necessary correction.Each mLof 0.05MEdetate disodium titrantis equivalent to 6.667mg of AlCl3.