Chemical Name:?BORAX?(Sodium Borate)????????????????RM Control No.:__________

PARAMETERS

??? USP-NF

STANDARD

SAMPLE

REMARKS

Description

Colorless, transparent crystals or white, crystalline powder.?Is odorless. Its solutions are alkaline to phenolphthalein TS As it effloresces in warm, dry air, the crystals are often coated with white powder

Solubility

Soluble in water

Freely soluble in boiling water?and in glycerin

Insoluble in alcohol

Identification

A 1 in 20 solution responds to tests for Sodium and Borate (191).

Carbonate and Bicarbonate

To 5ml of a solution (1 in 20), contained in a test tube, add 1ml of 3N HCl: no effervescence is observed

Heavy metals Method I <231>

The limit is 0.002%

Organic volatile impurities Method I <467>

Meets the requirements

Assay

Dissolve about 3g of sodium borate, accurately weighed, in 50ml of water, add methyl red TS, and titrate with 0.5N HCl VS.?Each ml of 0.5N HCl is equivalent to 72.84mg of Na₂B₄O₇.10H₂O.?Not less than 99.0% and not more than 105.0% Na₂B₄O₇.