Potassium Chloride
KCl 74.55
Potassium chloride.
Potassium chloride [7447-40-7].
» Potassium Chloride contains not less than 99.0 percent and not more than 100.5 percent of KCl, calculated on the dried basis.
Packaging and storage— Preserve in well-closed containers.
Labeling— Where Potassium Chloride is intended for use in hemodialysis, it is so labeled.
Identification— A solution (1 in 20) responds to the tests for Potassium 191 and for Chloride 191.
Acidity or alkalinity— To a solution of 5.0 g in 50 mL of carbon dioxide–free water add 3 drops of phenolphthalein TS: no pink color is produced. Then add 0.30 mL of 0.020 N sodium hydroxide: a pink color is produced.
Loss on drying 731— Dry it at 105 for 2 hours: it loses not more than 1.0% of its weight.
Iodide or bromide—
iodide—
Standard stock solution— Transfer an accurately weighed quantity, about 41 mg, of potassium iodide to a 25-mL volumetric flask. Dissolve in and dilute with water to volume, and mix.
Standard solution— Dilute 1.0 mL of Standard stock solution with water to 25 mL, and mix. Dilute 2.0 mL of this solution with water to 8 mL, and proceed as directed for Test solution beginning with “Add 1 mL each of chloroform”.
Test solution— Dissolve 2 g of Potassium Chloride in 8 mL of water. Add 1 mL each of chloroform and diluted hydrochloric acid, then add 2 drops of a chloramine T solution (0.1 in 100), and shake gently. The violet color of the chloroform layer is not darker than that of a concomitantly prepared Standard solution: the limit is 0.005%.
bromide—
Standard solution— Transfer an accurately weighed quantity, about 32 mg, of sodium bromide to a 25-mL volumetric flask. Dissolve in and dilute with water to volume, and mix. Dilute 2.0 mL of this solution with water to 8 mL, and proceed as directed for Test solution beginning with “Add 1 mL each of chloroform”.
Test solution— Dissolve 2 g of Potassium Chloride in 8 mL of water. Add 1 mL each of chloroform and diluted hydrochloric acid, then add 5 drops of a chloramine T solution (1 in 100), and shake gently. The brown color of the chloroform layer is not darker than that of a concomitantly prepared Standard solution: the limit is 0.1%.
Aluminum 206 (where it is labeled as intended for use in hemodialysis)— Proceed as directed using 2.0 g of Potassium Chloride to prepare the Test Preparation: the limit is 1 µg per g.
Calcium and magnesium— To 20 mL of a solution (1 in 100) add 2 mL each of 6 N ammonium hydroxide, ammonium oxalate TS, and dibasic sodium phosphate TS: no turbidity is produced within 5 minutes.
Sodium— A solution (1 in 20), tested on a platinum wire, does not impart a pronounced yellow color to a nonluminous flame.
Heavy metals 231— Dissolve 2.0 g in 25 mL of water: the limit is 0.001%.
Assay— Dissolve about 200 mg of Potassium Chloride, accurately weighed, in 10 mL of water. Add 10 mL of glacial acetic acid, 75 mL of methanol, and 3 drops of eosin Y TS. Titrate, with shaking, with 0.1 N silver nitrate VS to a pink endpoint. Each mL of 0.1 N silver nitrate is equivalent to 7.455 mg of KCl.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Daniel K. Bempong, Ph.D.
Senior Scientist
1-301-816-8143		 (MDPS05) Monograph Development-Pulmonary and Steroids
USP32–NF27 Page 3336
Pharmacopeial Forum: Volume No. 29(5) Page 1562
Chromatographic Column—
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.