Sodium Citrate Ph Eur.
Trisodium Citrate Ph Eur.
C6H5Na3O7,2H2O -- 294.1 -- 6132-04-3
DEFINITION
Trisodium 2-hydroxypropane-1,2,3-tricarboxylate dihydrate.
Content:
99.0 per cent to 101.0 per cent (anhydrous substance).
CHARACTERS
Appearance:
White or almost white, crystalline powder or white or almost white, granular crystals, slightly deliquescent in moist air.
Solubility:
Freely soluble in water, practically insoluble in ethanol (96 per cent).
IDENTIFICATION
A. To 1 ml of solution S (see Tests) add 4 ml of water. The solution gives the reaction of citrates.
B. 1 ml of solution S gives reaction of sodium.
TESTS
Solution S:
Dissolve 10.0 g in carbon dioxide-free water R prepared from distilled water R and dilute to 100 ml with the same solvent.
Appearance of solution:
Solution S is clear and colourless.
Acidity or alkalinity:
To 10 ml of solution S add 0.1 ml of PhPh solution. Not more than 0.2 ml of 0.1M hydrochloric acid or 0.1 M sodium hydroxide is required to change the colour of the indicator.
Readily carbonizable substances:
To 0.20 g of the powdered substance to be examined add 10 ml of sulphuric acid and heat in a water-bath at 90 ± 1 °C for 60 min. Cool rapidly. The solution is not more intensely coloured than reference solution.
Chlorides:
Maximum 50 ppm.
Oxalates:
Maximum 300 ppm.
Sulphates:
Maximum 150 ppm.
Heavy metals:
Maximum 10 ppm.
Water:
11.0 per cent to 13.0 per cent, determined on 0.300 g. After adding the substance to be examined, stir for 15 min before titrating.
Sodium Citrate IP Grade
We also make IP grade of Sodium Citrate
C6H5Na3O7 (anhydrous) 258.07
1,2,3-Propanetricarboxylic acid, 2-hydroxy-, trisodium salt.
Trisodium citrate (anhydrous) [68-04-2]
Trisodium citrate dihydrate 294.10 [6132-04-3]
Sodium Citrate is anhydrous or contains two molecules of water of hydration. It contains not less than 99.0 percent and not more than 100.5 percent of C6H5Na3O7, calculated on the anhydrous basis.
Identification:
A: A solution (1 in 20) responds to the tests for Sodium and for Citrate.
B: Upon ignition, it yields an alkaline residue which effervesces when treated with 3 N hydrochloric acid.
Alkalinity: A solution of 1.0 g in 20 mL of water is alkaline to litmus paper, but after the addition of 0.20 mL of 0.10 N sulfuric acid no pink color is produced by 1 drop of PhPh.
Water: Dry it at 180 for 18 hours: the anhydrous form loses not more than 1.0%, and the hydrous form between 10.0% and 13.0%, of its weight.
Tartrate: the limit is 0.001%.
Trisodium Citrate
C6H5Na3O7 Formula wt, anhydrous 258.07
C6H5Na3O7·2H2O Formula wt, dihydrate 294.10
INS: 331(iii) CAS: anhydrous [68-04-2]
CAS: dihydrate [6132-04-3]
DESCRIPTION
Sodium Citrate occurs as colorless crystals or as a white, crystalline powder. It is anhydrous or contains two molecules of water of crystallization. One gram of the dihydrate dissolves in 1.5 mL of water at 25° and in 0.6 mL of boiling water. It is insoluble in alcohol.
REQUIREMENTS
Identification: A 1:20 aqueous solution gives positive tests for Sodium and for Citrate.
Assay: Not less than 99.0% and not more than 100.5% of C6H5Na3O7, calculated on the anhydrous basis.
Alkalinity: Passes test.
Lead: Not more than 2 mg/kg.
Water: Anhydrous: Not more than 1%; Dihydrate: Between 10.0% and 13.0%.
Sodium Citrate Anhydrous is offered with very low moisture content.
