Expectorants – Pharmaceutical Inorganic Chemistry B. Pharma 1st Semester

Expectorants

Expectorants

Contents

• Expectorants:

• The monograph analysis of:

 Ammonium chloride

 Potassium iodide

Learning Objectives

At the end of this lecture, the student will be able to:

• Define: Expectorants:

• Explain the monograph analysis of:

 Ammonium chloride

 Potassium iodide

Expectorants

Expectorants: help in removing the sputum from respiratory tract.

Classification of expectorants:

• Sedative

• Stimulant

The inorganic compound used as expectorant are ammonium chloride and potassium iodide

Monograph of Ammonium chloride

Name: Ammonium chloride

Chemical formula: NH4Cl

Molecular weight: 53.5

Standard: Ammonium Chloride contains not less than 99.0 per cent and not more than 100.5 per cent of NH4Cl, calculated on the dried basis

Method of preparation:

CO2 +2NH3 + 2 NaCl + H2O à 2NH4Cl + Na2CO3

Properties of ammonium chloride:

Description:

Colourless crystals or a white, crystalline powder.

Monograph of Ammonium chloride contd—

Test for purity:

Appearance of solution

Sulphates

pH

Thiocyanate

Sulphated ash

Arsenic

Heavy metals

Loss on drying

Iron

Calcium

Assay:

Principle Acid/Base titration

NH4Cl     + H2O  à NH4OH   + HCl

4NH4OH + 6HCHO à (CH2)6N4 +   10 H2O

NaOH + HCl à NaCl +H2O

Indicator: phenolphthalein

Colour change: colorless to pale pink

Medicinal uses:

• Expectorant

Storage: store protected from light and moisture

Monograph of Potassium iodide

Name: Potassium iodide

Chemical formula: KI

Molecular weight: 166.0

Standards: Potassium Iodide contains not less than 99.0 per cent and not more than 100.5 per cent of KI, calculated on the dried basis

Method of preparation:

Step: I 6 KOH + 3 I2 → KIO3 + 5 KI + 3 H2O

Step: II KIO3 + 3 C → KI + 3 CO

Properties of potassium iodide

Description: Colourless crystals or a white powder; odourless

Test for purity

Iodate

Appearance of solution

Alkalinity

Arsenic

Heavy metals

Iron

Barium

Cyanide

Sulphates

Thiosulphate

Loss on drying

Assay: Principle Iodometric titration

Indicator: Chloroform

Colour change: purple to colourless

Storage: store protected from light and moisture

Summary:

• Expectorants: removes sputum

• Ammonium chloride: Prepared by passing ammonia gas through a solution of hydrochloric acid, assayed by formal titration method and medicinally used as an expectorant

• Potassium iodide: Prepared by passing iodine gas through a solution of potassium hydroxide, assayed by iodometric titration using chloroform as an indicator

Also, Visit:

B. Pharma Notes | B. Pharma Notes | Study material Bachelor of Pharmacy pdf

B. Pharma Handwritten Notes

B. Pharma PDF Books

B. Pharma Lab Manual

D. Pharma Lab Manual

B. Pharma 8th Semester Previous Year Question Paper

D. Pharma Notes

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