Ammonium Chloride

Ammonium Chloride (NH_4Cl) is an inorganic compound commonly used in various industrial and medical applications. It is a white crystalline salt that is highly soluble in water. Ammonium chloride is known for its expectorant properties in medicine and as a flux in metallurgy.

Properties

Ammonium chloride is a white crystalline solid that is highly soluble in water. Its solutions are slightly acidic. This compound sublimes upon heating and can decompose into ammonia and hydrogen chloride when exposed to high temperatures.

Production

Ammonium chloride is primarily produced by combining ammonia (NH_3) with hydrochloric acid (HCl):

NH_3 + HCl → NH_4Cl

This reaction is exothermic, releasing heat. The compound can also be obtained as a by-product in the Solvay process, which is used to produce sodium carbonate.

Applications

Medical Use

In medicine, ammonium chloride is used as an expectorant in cough medicine to help clear mucus from the airways. It works by increasing the volume of bronchial secretions, improving the efficiency of the cough reflex and facilitating the removal of phlegm.

Industrial Use

In the industrial sector, ammonium chloride serves as a flux in preparing metals to be tin coated, galvanized, or soldered. It works by cleaning the metal surface to ensure a good bond between the metal and the solder.

Other Uses

Ammonium chloride is also used in:

• The food industry as a food additive under the European food additive code E510, acting as a yeast nutrient in breadmaking.
• The textile and leather industry in dyeing, tanning, textile printing, and to luster cotton.
• As a component in dry cell batteries, where it acts as an electrolyte.

Safety and Environmental Impact

Ammonium chloride is generally regarded as safe for use in various applications. However, it can be irritating to the eyes, skin, and respiratory system upon contact or inhalation of its dust. Proper safety measures should be taken to avoid exposure.

Environmental concerns with ammonium chloride are minimal when handled properly, but it can contribute to the nitrogen load in water bodies, potentially leading to eutrophication.

See Also

• Ammonia
• Hydrochloric acid
• Solvay process