The amount of strong acid added to a buffer solution cannot exceed the original amount of conjugate base present in order for the buffer to still work.

Question

Quizplus · Accepted Answer

A buffer solution works by having a pair of a weak acid and its conjugate base in equilibrium. If a strong acid is added, it will react with the conjugate base, shifting the equilibrium towards forming more weak acid. However, if all the conjugate base is consumed, the buffer will no longer be able to resist changes in pH, making it ineffective. Therefore, the amount of strong acid added cannot exceed the original amount of conjugate base for the buffer to still work.

The Amount of Strong Acid Added to a Buffer Solution