Sodium Nitrite BP Pharmacopoeia
NaNO2
DEFINITION
Content
98.5 per cent to 100.5 per cent (dried substance).
CHARACTERS
Appearance:
Colourless crystals or mass or yellowish rods, hygroscopic.
Solubility: Freely soluble in water, soluble in alcohol.
IDENTIFICATION
A. Dilute 1 ml of solution S1 (see Tests) to 25 ml with water R. To 0.1 ml of the
solution add 1 ml of sulphanilic acid solution. Allow to stand for 2-3 min. Add 1 ml
of b-naphthol solution and 1 ml of dilute sodium hydroxide solution R. An intense
red colour develops.
B. To 1 ml of the solution prepared for identification test A add 3 ml of a 20 g/l
solution of phenazone and 0.4 ml of dilute sulphuric acid. An intense green colour
develops.
C. To 0.15 ml of solution S1, add 0.35 ml of water R. The solution gives reaction of
sodium.
TESTS
Solution S1:
Dissolve 2.5 g in carbon dioxide-free water and dilute to 50 ml with the same
solvent.
Solution S2:
Dissolve 3 g in distilled water. Cautiously add 10 ml of nitric acid and evaporate
to dryness. Dissolve the residue in 10 ml of distilled water R, neutralize with
dilute sodium hydroxide solution  and dilute to 30 ml with distilled
water.
Appearance of solution:
Solution S1 is clear and not more intensely coloured than reference solution.
Acidity or alkalinity:
To 10 ml of solution S1, add 0.05 ml of phenol red solution. Add 0.1 ml of 0.01 M
sodium hydroxide. The solution is red. Add 0.3 ml of 0.01 M hydrochloric acid. The
solution is yellow.
Chlorides:
Maximum 50 ppm.
Dilute 10 ml of solution S2 to 15 ml with water. The solution complies with the
limit test for chlorides.
Sulphate:
Maximum 200 ppm.
Heavy metals:
Maximum 20 ppm.
Loss on drying:
Maximum 1.0 per cent, determined on 1.000 g by drying in vacuum.
Sodium Nitrite USP
NaNO2 69.00
Nitrous acid, sodium salt.
Sodium nitrite CAS 7632-00-0
Sodium Nitrite contains not less than 97.0 percent and not more than 101.0 percent of NaNO2, calculated on the dried basis.
Identification— A solution of it responds to the tests for Sodium and for
Nitrite.
Loss on drying— Dry it over silica gel for 4 hours: it loses not more than
0.25% of its weight.
Heavy metals— Dissolve 1 g in 6 mL of 3 N hydrochloric acid, and evaporate
on a steam bath to dryness. Reduce the residue to a coarse powder, and continue
heating on the steam bath until the odor of hydrochloric acid no longer is
perceptible. Dissolve the residue in 23 mL of water, and add 2 mL of 1 N acetic
acid: the limit is 0.002%.
Assay— Dissolve about 1 g of Sodium Nitrite, accurately weighed, in water
to make 100.0 mL. Pipette 10 mL of this solution into a mixture of 50.0 mL of 0.1 N
potassium permanganate VS, 100 mL of water, and 5 mL of sulfuric acid. When adding
the Sodium Nitrite solution, immerse the tip of the pipette beneath the surface of
the permanganate mixture. Warm the liquid to 40 , allow it to stand for 5 minutes,
and add 25.0 mL of 0.1 N oxalic acid VS. Heat the mixture to about 80 , and titrate
with 0.1 N potassium permanganate VS. Each mL of 0.1 N potassium permanganate is
equivalent to 3.450 mg of NaNO2.
Sodium Nitrite FCC Food Grade
NaNO2 Formula wt 69.00
INS: 250 CAS 7632-00-0
DESCRIPTION
Sodium Nitrite occurs as a white to slightly yellow, granular powder, or as white or
nearly white, opaque, fused masses or sticks. It is hygroscopic in air. Its
solutions are alkaline to litmus. One gram dissolves in 1.5 mL of water, but it is
sparingly soluble in alcohol.
Function: Color fixative in meat and meat products; antimicrobial agent;
preservative.
REQUIREMENTS
Identification: An aqueous solution gives positive tests for Sodium and for
Nitrite.
Assay: Not less than 97.0% and not more than 100.5% of NaNO2 after
drying.
Lead: Not more than 4 mg/kg.
Loss on Drying: Not more than 0.25%.
Sodium Nitrite ACS Reagent
NaNO2
Formula Weight 69.00
CAS Number 7632-00-0
REQUIREMENTS
Assay: 97.0% NaNO2 min
MAXIMUM ALLOWABLE
Insoluble matter: 0.01%
Chloride (Cl): 0.005%
Sulfate (SO4): 0.01%
Calcium (Ca): 0.01%
Potassium (K): 0.005%
Heavy metals (as Pb): 0.001%
Iron (Fe): 0.001%
