Sodium hydroxide is sometimes called caustic soda or lye. It is a common ingredient in cleaners and soaps. At room temperature, sodium hydroxide is a white, odorless solid. Liquid sodium hydroxide is colorless and has no odor. It can react violently with strong acids and water. Sodium hydroxide is corrosive.
NaOH can react with moisture from the air and may generate heat as it dissolves. This heat can be enough to cause a fire if it is near flammable materials.
Sodium hydroxide is useful for its ability to alter fats. It is used to make soap and as a main ingredient in household products such as liquid drain cleaners.
Sodium hydroxide is usually sold in pure form as white pellets or as a solution in water.