Packaging and storage—
Preserve in well-closed containers.
Labeling—
The label states the content of anhydrous aluminum chlorohydrate.
Identification—
A:
A solution (1 in 10) responds to the tests for
Aluminum 
191
and for
Chloride 191.
Test specimen—
Dissolve 0.5 g in about 40 mL of water, and while mixing adjust with 2.5 N sodium hydroxide to a pH of 9.55 ± 0.05. Filter the suspension of precipitate thus obtained. Evaporate about 15 mL of the filtrate to about 1 mL on a hot plate. Deposit this solution on a silver chloride disk.
Standard specimen:
a similar preparation of polyethylene glycol.
pH 791:
between 3.0 and 5.0, in a solution [15 in 100 (w/w)].
Limit of iron—
Using Aluminum Chlorohydrex Polyethylene Glycol instead of Aluminum Chlorohydrate, proceed as directed in the test for
Limit of iron under
Aluminum Chlorohydrate. The limit is 150 µg per g.
Aluminum/chloride atomic ratio—
Divide the percentage of aluminum found in the test for
Content of aluminum by the percentage of chloride found in the test for
Content of chloride, and multiply by 35.453/26.98, in which 35.453 and 26.98 are the atomic weights of chlorine and aluminum, respectively: the ratio is between 1.91:1 and 2.10:1.
Assay—
Calculate the percentage of anhydrous aluminum chlorohydrate in the Aluminum Chlorohydrex Polyethylene Glycol by the formula:
Al({26.98
x + [17.01(3
x 
1)] + 35.453} / 26.98
x),
in which
Al is the percentage of aluminum found in the test for
Content of aluminum,
x is the aluminum/chloride atomic ratio found in the test for
Aluminum/chloride atomic ratio, 26.98 is the atomic weight of aluminum, 17.01 is the molecular weight of the hydroxide anion (OH), and 35.453 is the atomic weight of chlorine (Cl).
