EUROPEAN PHARMACOPOEIA 9.0
Ammonium chloride
Column:
- size: I = 0.25 m, 0 = 2 mm;
- stationary phase: strongly basic anion-exchange resin for chromatography R (13 urn).
Mobile phase: dissolve 0.600 g of potassium hydroxide R in water for chromatography R and dilute to 1000.0 mL with the same solvent.
Flow rate: 0.4 mL/min.
Detection: conductivity detector equipped with a suitable ion suppressor.
Injection: 50 uL of test solution (b), reference solutions (a) and (b) and the blank solution.
Run time: 2.5 times the retention time of bromide.
Retention time: chloride - about 5 min; bromide - about 8 min; sulfate - about 16 min.
System suitability: reference solution (b):
- resolution: minimum 8.0 between the peaks due to chloride and bromide.
Calculation of percentage contents:
- for chlorides, use the concentration of chloride in reference solution (a); correct the area of the peak due to chloride in the chromatogram obtained with reference solution (a) by subtracting the area of the peak due to chloride in the chromatogram obtained with test solution (b);
- for sulfates, use the concentration of sulfate in reference solution (a); correct the area of the peak due to sulfate in the chromatogram obtained with reference solution (a) by subtracting the area of the peak due to sulfate in the chromatogram obtained with test solution (b).
Limits:
- chlorides: maximum 0.6 per cent;
- sulfates: maximum 0.01 per cent.
Iodides. To 5 mL of solution S add 0.15 mL of ferric chloride solution Rl and 2 mL of methylene chloride R. Shake and allow to separate. The lower layer is colourless {2.2.2, Method I).
Iron (2.4.9): maximum 20 ppm.
Dilute 5 mL of solution S to 10 mL with water R.
Magnesium and alkaline-earth metals (2.4.7): maximum 200 ppm, calculated as Ca.
10.0 g complies with the test for magnesium and alkaline-earth metals. The volume of 0.01 M sodium edetate used does not exceed 5.0 mL.
Loss on drying {2.2.32): maximum 1.0 per cent, determined on 1.000 g by drying in an oven at 105 °C,
Sulfated ash (2.4.14): maximum 0.1 per cent, determined on 1.0 g.
ASSAY
Dissolve 80.0 mg in water R, add 5 mL of dilute nitric acid R and dilute to 50 mL with water R. Titrate with 0.1 M silver nitrate, determining the end-point potentiometrically (2.2.20).
1 mL of 0.J M silver nitrate is equivalent to 9.794 mg of NH,Br.
Calculate the percentage content of NH;1Br using the following expression:
a - 2.763 b
a      -   percentage content of NH.,Br and NH4C1 obtained in the assay and calculated as NH,Br;
b      =   percentage content of CI obtained in the test for chlorides.
STORAGE
In an airtight container, protected from light. „1BB..... 01/2017:0007
AMMONIUM CHLORIDE
Ammonii chloridum
NH4C1 Mr 53.49
[12125-02-9]
DEFINITION
Content: 99.0 per cent to 100.5 per cent (dried substance). CHARACTERS
Appearance: white or almost white, crystalline powder or colourless crystals.
Solubility: freely soluble in water. IDENTIFICATION
A. It gives the reactions of chlorides (2.3.1).
B. 10 mL of solution S (see Tests) gives the reaction of ammonium salts (2.3.1).
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 (2.2.1) and colourless (2.2.2, Method II).
Acidity or alkalinity. To 10 mL of solution S add 0.05 mL of methyl red solution R. Not more than 0.5 mL of 0.01 M hydrochloric acid or 0.01 M sodium hydroxide is required to change the colour of the indicator.
Bromides and iodides. To 10 mL of solution S add 0.1 mL of dilute hydrochloric acid R and 0.05 mL of chloramine solution R. After 1 min, add 2 mL of chloroform R and shake vigorously. The chloroform layer remains colourless (2.2.2, Method I).
Sulfates (2.4.13): maximum 150 ppm.
Dilute 10 mL of solution S to 15 mL with distilled water R.
Calcium (2.4.3): maximum 200 ppm.
Dilute 5 mL of solution S to 15 mL with distilled water R.
Iron (2.4.9): maximum 20 ppm.
Dilute 5 mL of solution S to 10 mL with water R.
Loss on drying (2.2.32): maximum 1.0 per cent, determined on 1.00 g by drying in an oven at 105 °C for 2 h.
Sulfated ash (2.4.14): maximum 0.1 per cent, determined on 2.0 g.
ASSAY
Dissolve 1.000 g in 20 mL of water R and add a mixture of 5 mL offormaldehyde solution R, previously neutralised to phenoiphthalein solution R, and 20 mL of water R. After 1-2 min, titrate slowly with 1 M sodium hydroxide, using a further 0.2 mL of the same indicator.
1 mL of I M sodium hydroxide is equivalent to 53.49 mg of NH4C1.
General Notices (I) apply to all monographs and other texts
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