Sodium Hypochlorite Solution
NaClO 74.44

Hypochlorous acid, sodium salt.
Sodium hypochlorite [7681-52-9].
» Sodium Hypochlorite Solution contains not less than 4.0 percent and not more than 6.0 percent, by weight, of NaClO.
Caution—This Solution is not suitable for application to wounds.
Packaging and storage— Preserve in tight, light-resistant containers, at a temperature not exceeding 25.
Identification—
A: The Solution at first colors red litmus blue and then bleaches it.
B: The addition of 3 N hydrochloric acid to the Solution causes an evolution of chlorine.
C: The solution obtained in Identification test B responds to the flame test for Sodium 191.
Assay— Weigh accurately, in a glass-stoppered flask, about 3 mL of Solution, and dilute it with 50 mL of water. Add 2 g of potassium iodide and 10 mL of 6 N acetic acid, and titrate the liberated iodine with 0.1 N sodium thiosulfate VS, adding 3 mL of starch TS as the endpoint is approached. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N sodium thiosulfate is equivalent to 3.722 mg of NaClO.
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Topic/Question Contact Expert Committee
Monograph Radhakrishna S Tirumalai, Ph.D.
Senior Scientist
1-301-816-8339
(GTMDB05) General Toxicology and Medical Device Biocompatibility
USP32–NF27 Page 3576