Sodium hydroxide

Sodium hydroxide (lye) is a white crystalline solid that forms a strong base in water and has a wide range of uses. Chemically, it is an ionic compound composed of a sodium ion (Na) and a hydroxide ion (OH).

Uses
Sodium hydroxide's uses include:
 * adjust the pH of a solution. This is often done as a last step to neutralize any deviation from the expected pH. Sodium hydroxide is well suited to this purpose because the only byproduct is sodium ions.