Caustic soda, also known as sodium hydroxide or lye, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations Na+ and hydroxide anions OH−. Sodium hydroxide is a highly caustic base and alkali that decomposes proteins at ordinary ambient temperatures and may cause severe chemical burns. It is highly soluble in water, and readily absorbs moisture and carbon dioxide from the air. Its Caustic chemical formula forms a series of hydrates: NaOH·nH2O. The monohydrate NaOH·H2O crystallizes from water solutions between 12.3 and 61.8 °C. The commercially available “sodium hydroxide” is often this monohydrate, and published data may refer to it instead of the anhydrous compound “caustic soda”.
Caustic Soda Uses
An extremely versatile household product, caustic soda is mainly used as a drain pipe cleaner, to unblock drains, remove grease buildup from ovens, and to make soap and detergents. As one of the simplest hydroxides, it is also frequently utilized alongside neutral water and acidic hydrochloric acid to demonstrate the pH scale in soda caustic to chemistry students.