Ammonium Chloride

(Ph Eur monograph 0007)

 

NH4Cl      53.49      12125-02-9

 

Ph Eur


 

 

Definition

 

Ammonium chloride contains not less than 99.0 per cent and not more than the equivalent of 100.5 per cent of NH4Cl, calculated with reference to the dried substance.

 

Characters

 

A white, crystalline powder or colourless crystals, 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 0.01M hydrochloric acid or 0.01M 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).

 

Sulphates (2.4.13)

 

10 ml of solution S diluted to 15 ml with distilled water  R complies with the limit test for sulphates (150 ppm).

 

Calcium (2.4.3)

 

5 ml of solution S diluted to 15 ml with distilled water  R complies with the limit test for calcium (200 ppm).

 

Iron (2.4.9)

 

5 ml of solution S diluted to 10 ml with water  R complies with the limit test for iron (20 ppm).

 

Heavy metals (2.4.8)

 

12 ml of solution S complies with limit test A (10 ppm). Prepare the standard using lead standard solution (1 ppm Pb) R.

 

Loss on drying (2.2.32)

 

Not more than 1.0 per cent, determined on 1.00 g by drying in an oven at 100-105C for 2 h.

 

Sulphated ash (2.4.14)

 

Not more than 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 of formaldehyde solution R, previously neutralised to phenolphthalein solution R, and 20 ml of water  R. After 1 min to 2 min, titrate slowly with 1M sodium hydroxide, using a further 0.2 ml of the same indicator.

 

1 ml of 1M sodium hydroxide is equivalent to 53.49 mg of NH4Cl.

 

 

 


Ph Eur

 

Action and use

 

Used for the acidification of urine and to correct metabolic alkalosis.

 

Preparation

 

Ammonium Chloride Mixture