タイトルまたは説明

Boric Acid BP

H3BO3 *- *1.8 *- *********3
Boric Acid BP

DEFINITION
Boric acid contains not less than *9.0 per cent and not more than the equivalent of **0.5 percent of H3BO3.

CHARACTERS
A white, crystalline powder, colourless, shiny plates greasy to the touch, or white  crystals, soluble in water and in alcohol, freely soluble in boiling water and in glycerol  (*5 per cent).

IDENTIFICATION
A. Dissolve 0.1 g by gently heating in 5 ml of methanol, add 0.1 ml of sulphuric acid and ignite the solution. The flame has a green border.
B. Solution S (see Tests) is acid.

TESTS
Solution S
Dissolve 3.3 g in *0 ml of boiling distilled water, cool and dilute to **0 ml with  carbon dioxide-free water prepared from distilled water.
Appearance of solution
Solution S is clear and colourless.
pH
The pH of solution S is 3.8 to 4.8.
Solubility in alcohol
Dissolve 1.0 g in *0 ml of boiling alcohol. The solution is not more opalescent than reference suspension and is colourless.
Organic matter
It does not darken on progressive heating to dull redness.
Sulphates
*0 ml of solution S diluted to *5 ml with distilled water complies with the limit test  for sulphates (**0 ppm).
Heavy metals
*2 ml of solution S complies with limit test A for heavy metals (*5 ppm).

Boric Acid USP NF

H3BO3 *- *1.*3
Boric acid USP-NF (H3BO3) [*********3].

Boric Acid contains not less than *9.5 percent and not more than **0.5 percent of H3BO3, calculated on the dried basis.

Solubility in alcohol— One g dissolves completely in *0 mL of boiling alcohol.
Completeness of solution— One g dissolves in *5 mL of water, producing a clear solution.
Identification— It responds to the tests for Borate.
Loss on drying— Dry it over silica gel for 5 hours: it loses not more than 0.5% of its weight.
Heavy metals— Dissolve 1 g in *3 mL of water, and add 2 mL of 1 N acetic acid: the limit is 0.**2%.

ACS Specifications
American Chemical Society

Boric Acid ACS Analytical Reagent

H3BO3
Formula Wt *1.*3
CAS Number *********3

REQUIREMENTS
Assay: *9.5% H3BO3

MAXIMUM ALLOWABLE
Insoluble in methanol .......... 0.**5%
Nonvolatile with methanol ... 0.*5%
Chloride (Cl) ...................... 0.**1%
Phosphate (PO4) ................ 0.**1%
Sulfate (SO4) ..................... 0.*1%
Calcium (Ca) ..................... 0.**5%
Heavy metals (as Pb) ......... 0.**1%
Iron (Fe) ...........................  0.**1%