Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 exam•Written by the Fiveable Content Team • Last updated September 2025
Definition
Sodium hydroxide (NaOH) is an inorganic compound commonly known as caustic soda or lye. It is highly soluble in water and forms an alkaline solution when dissolved.
Related terms
Hydroxide Ion: A negatively charged ion consisting of one oxygen atom bonded with one hydrogen atom (-OH). It gives sodium hydroxide its alkaline properties.
Substances like sodium hydroxide that completely dissociate into their constituent ions when dissolved in water, resulting in high concentrations of hydroxide ions.
Corrosive: Describes substances like sodium hydroxide that can cause severe damage, such as burns, due to their ability to chemically react with and destroy living tissues.