What Is the PKa of Sodium Hydroxide?

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Sodium hydroxide is a strong base with a 13.8 pKa value. Sodium hydroxide has a chemical formula of NaOH and is also referred to as lye or caustic soda. It is an organic compound and alkali salt.

According to James Ashenhurst of Master Organic Chemistry, sodium hydroxide is the conjugate base of water. Water is a weak acid with a 15.7 pKa value. Sodium hydroxide reacts with protic acids, such as hydrochloric acid, to produce water and the corresponding salt. In the case of a reaction with hydrochloric acid, water and sodium chloride are the products formed. Hydrochloric acid or HCL is a strong acid with a pKa value of -8. This difference between water and HCL is approximately 24 pKa. With such a large pKa difference, this acid-base reaction is favored and is essentially irreversible.