Question

Hydrochloric acid is a strong acid and carbonic acid is a weak acid. Yet 1 L of 1 M HCl solution will neutralize 1 mole of NaOH and 1 M of carbonic acid will neutralize 2 moles of NaOH. Explain.

Answer 1

A mixture of a weak acid and its conjugate base is called a buffer solution, or a buffer. Buffer solutions resist a change in pH when small amounts of a strong acid or a strong base are added.

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