Which chemical compound is also known as caustic soda?

The chemical compound also known as caustic soda is sodium hydroxide.

Sodium hydroxide has the formula NaOH and is a strong base. It is usually encountered as a white solid that absorbs moisture from the air and dissolves readily in water, releasing heat. The name “caustic” refers to its ability to cause severe chemical burns.

Industrially, sodium hydroxide is made mainly by the chloralkali process, which electrolyzes brine to produce sodium hydroxide, chlorine, and hydrogen. It is used to make paper, soap, detergents, textiles, alumina, and many other chemicals. Drain cleaners may contain it because it can break down fats and some organic materials.

Sodium hydroxide is often confused with sodium carbonate, also called washing soda. Both are alkaline sodium compounds, but sodium hydroxide is much more corrosive. Potassium hydroxide is a related strong base called caustic potash.