Boric Acid

MOLECULAR FORMULA :- H3BO3

MOLECULAR WEIGHT :- 61.83

SPECIFICATION IP BP USP
Description White, Crystalline powder or colorless shiny plates, unctuous to the touch or white crystals, odorless White or almost white, crystalline powder, colorless, shiny plates greasy to the touch, or white or almost white crystals. White or almost white, crystalline powder, colorless, shiny plates greasy to the touch, or white or almost white crystals.
Solubility Soluble in water and in ethanol (96 %), freely soluble in boiling water and in glycerol ( 85 %).
Appearance of solution

(10% w/v solution)

3.5 % w/v solution in boiling water is clear and colorless. 3.3 % w/v solution is clear and color less.
Identification

(A)     By color

(B)    Reaction

A: The flame has a green border.

B: 3.3 %w/v the solution is faintly acid.

A: The flame has green border.

B: 3.3 % w/v solution is acidic.

 

It responds to the tests for borate
Ph ( 3.3 % w/v solution) 3.8-4.8 3.8 – 4.8
Solubility in ethanol

(96% )

The solution is not more opalescent than opalescence standard OS2 and colorless The solution has not more opalescent than reference suspension II and colorless.
Organic matter It does not darken on progressive heating to dull redness
Sulphates NMT 450 ppm NMT 450  ppm
Arsenic NMT 10 ppm
Heavy metal NMT 20 ppm NMT 20 ppm
Loss on drying NMT 0.5 % NMT 0.5 %
Residual solvents Meets the requirements
Assay 99.5 % to 100.5 % ( on dry basis) 99.0  % – 100.5  % 99.5 % to 100.5% (on dry basis )