Sodium hydroxide

Caustic soda, with formula NaOH

Sodium hydroxide, also known as caustic soda and, more generically, as 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−. As a strong nucleophile, it is frequently used in SN2 reactions. Sodium hydroxide is a highly corrosive base and alkali that decomposes lipids and proteins at ambient temperatures, and may cause severe chemical burns at high concentrations.

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