Sodium hydroxide is a white translucent crystalline solid. Its aqueous solution has astringent and slippery feel.
Water absorption (deliquescent): Sodium hydroxide is easily deliquescent in the air, so solid sodium hydroxide is often used as a desiccant. However, liquid sodium hydroxide has no water absorption.
Very soluble in water, releasing a lot of heat when dissolved. Soluble in ethanol and glycerin.