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7/30/2019 Chloride - Copy

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Title: Pharmacopoeial Analysis of Sodium Chloride

Apparatus required:1)Burette, 2)Volumetric/graduate pipette, 3)Conical flasks, 4)Volumetric flasks(10ml),5)Nessler cylinders(50ml)

6)Hydrogen sulphide generator, 7)pH. Meter, 8)UV/Vis spectrophotometer, 9)A drying oven, 10)Beakers,

11)Volumetric flasks.

Chemicals reaquired:1)Bromothymol blue solution, 2)0.01M hydrochloric acid, 3)0.01M sodium hydroxide, 4)Dil. Sulphuric acid,

5)Phenol red solution, 6)Chloramine T(0.01%), 7)Potassium bromide, 8)Sodium thiosulphate(0.1M),

9)Eriochrome black T solution,10)EDTA(0.005M), 11)Strong ammonia-ammonium chloride solution, 12)Ferric

ammonium sulphate(1.0%w/v), 13)Ferrous sulphate(1.0%w/v), 14)Sulphuric acid(0.25%w/v), 15)Lead standardsolution (100ppm), 16)Hydrogen sulphide solution. 17)Dilute acetic acid, 18)Iodide-free starch solution,

19)Sodium nitrite solution, 20)Sulphuric acid(0.5M), 21)Potassium chromate solution(5.0%w/v), 22)Silver

nitrate(0.1M).

Theory:

Pharmacopoeias have their own distinctive format. Nonetheless, the monographs their in have much in common

in that their content is both descriptive and informative in addition to prescribing standards and conditions of

storage. The typical official monographs for pharmaceutical chemicals generally embrace the following:

1)A definition of the nature of material, 2)A statement of the minimum standard of purity as determined by assay

3) A description of its physical characteristics. 4) Tests for use in verifying the identity of the product, 5)Limit

tests to exclude excessive contamination and./or decomposition..6)Official quantitative procedures for

determination of the active ingredient, solvents and other constituents required to assess compliance with the

standard.7)Physical constants and tests which supplement the standard..8) Other information on: a)packaging and

storage conditions. b)labeling and other regulatory requirements(e.g. FDA). c)dosage cautionary notices on

cytotoxic and other such dangerous materials.

In general, statements under the headings 1,2,3(except solubilities), 4,5,6 and 7 constitute the official standards

and methods for the assessment of material bearing the name at the head of the monograph for use in humanmedicine and also, unless specified to the contrary, for veterinary use.

Procedure:

NaCl Mol. Wt. 58.4


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Sodium Chloride contains not less than 99.0 per cent and not more than 100.5 per cent of NaCl, calculated on the

dried basis.

Description. White or colourless crystals or a white crystallinepowder.

Solubilities. Freely soluble in water, practically insoluble in ethanol.

IdentificationA. Gives the reactions of chlorides( 2.3.1).B. A 20 per cent w/v solution in carbon dioxide-free water prepared from distilled water (solution A) gives the

reactions of sodium salts( 2.3.1).

Tests

Appearance of solution. Solution A is clear (2.4.1), and, colourless (2 .4.1).

Acidity or alkalinity. To 20 ml of solution A add 0.1 ml of bromothymol blue solution; not more than 0.5 ml of0.01 M hydrochloric acid or of 0.01 M sodium hydroxide is required to change the colour of the solution.

Barium. Dissolve 2g in 10ml of water. and add 2 ml of dilute sulphuric acid; no turbidity is produced within 2hours.

Bromide. To 0.5 ml of solution A add 4.0ml of water. 2.0 ml of phenol red reagent and 1.0 ml of 0.01 per cent

w/v solution of chloramines T and mix immediately. After exactly 2 minutes, add 0.15 ml of 0.1 M sodiumthiosulphate mix and dilute to 10.0m l with water. The absorbance of the solution measured at about 590 nm

(2.4.1), using water as the blank, is not more than that of the standard solution prepared at the same time

and in the same manner, using 5.0 ml of a 0.0003 per cent w/v solution of potassium bromide (100 ppm).

Calcium and magnesium. Not more than 50 ppm, calculated as Ca,determined by the following method.

Dissolve 20.0g in 200 ml of water, and add 0.1 ml of hydrochloric acid, 5 ml of strong ammonia-amrnonium

chloride solution,5 drops of eriochrome blackT solution and titrate with0.005 M disodium edetate to a blue end-point. 1 ml of 0.00 5 M disodium edetate is equivalent to 0.0002004 g of Ca.

Ferrocyanide. Dissolve 2.0 g in 6 ml of water and add 0.5 ml of a mixture of 5 ml of a 1 per cent w/v solution offerric ammonium sulphate in a 0.25 per cent w/v solution of sulphuric acid, and 95 ml of a 1 per cent w/v solutio

of ferrous sulphate;no blue colour is produced within l0 minutes.

Heavy metals (2.3.l3). 4.0 g in 2 ml of dilute acetic ac id and sufficient water to produce 25 ml. The solution

complies with the limit test for heavy metals, Merhod A (5 ppm).

Standard solution: Into a 50-ml Nessler cylinder pipette 1 .0 ml of lead standard solution (20 ppm Pb) and dilut

with water to 25 ml. Adjust with dilute acetic acid or dilute ammonia solution to a pH between 3.0 and 4.0, dilutwith water to about 35 ml and mix.Test solution: Into a 50-ml Nessler cylinder place 25 ml of the solution prepared for the test as directed in the

individual monograph or dissolve the specified quantity of the substance under examination in sufficient water to

produce 25 ml. Adjust with dilute acetic acid or dilute ammonia solution to a pH between 3.0 and 4 .0,d ilute witwith water to about 35m l and m ix.

To each of the cylinders containing the standard solution and test solution respectively add l0 ml of freshly


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prepared by hydrogen sulphide solution, m ix, dilutet to 50 ml with water, allow to stand for 5 minutes and view

downwards over a white surface; the colour produced with the test solution is not more intense than that produced

with the standard solution.

Iodide. Moisten 5 g by adding dropwise, a solution freshly prepared by mixing 25 ml of iodide-free starch

solution 2 ml of 0.5 M sulphuric acid,0.15 ml of sodium nitrite solution and, 25 ml of water and examine themixture in daylight; the substance shows no blue colour after 5 minutes.

Loss on drying (2.4. I 9). Not more than 1.0 per cent. Determined on 1.0g by drying in an oven at 105C fo r 3

hours.

Assay.

Weigh accuratelya bout0 .1 g and d issolve in 50 ml of water in a 250ml conical flask..A dd 1ml of potassiumchromate solution(5.0%w/v) as an indicator. Titrate against 0.1M silver nitrate V.S. with continuous shaking un

a light brown colour of silver chromate appears . Each millilitre of 0.1 M silver nitrate is equivalent to 0.005844

of NaCl.

Calculation:

Percentage purity of sodium chloride (on dried basis)

Sp1 . =Vol. of 0.1M silver nitrate consumed X f X 0.005844g X 100 %Wt. of sample taken(g)

Sp2 . =Vol. of 0.1M silver nitrate consumed X f X 0.005844g X 100 %

Wt. of sample taken(g)

Observations and results:S.No. Topics/Tests Specifications Observations

1. Descriptions White or colourless crystals or a white crystalline2. Solubilities Freely soluble in water, practically insoluble in

ethanol.

3. Identification A. Reactions of chlorides

B. Test for sodium salts

4. Appearance of solution Solution A is clear

5. Acidity or alkalinity ot more than 0.5 ml of 0.01 M hydrochloric acid

or 0.01 M sodium hydroxide


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6. Barium No turbidity is produced within 2 hrs.

7. Bromide Max. 100 ppm

8. Calcium and magnesium Max. 50ppm

9. Ferrocyanide No blue colour is produced within l0 minutes

10. Heavy metals Max. 5ppm

11. Iodide No blue colour after 5 minutes12. Loss on drying Not more than 1.0 per cent

13. Assay(on dried basis) 99.0 to 100.5%

Ressult with remarks:

The submitted sample complies/does not comply to the specifications with respect to the above tests.

Conclusion:

chloride - copy

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