Final answer:
Adding a strong acid or base to an acetate buffer like acetic acid-sodium acetate leads to reactions that neutralize the added substances, with minimal pH change due to shifts in ionization equilibrium.
Step-by-step explanation:
When you add a strong acid or strong base to an acetate buffer, the buffer system works to minimize changes in pH. In the case of a strong base like OH- being added, it will react with acetic acid to produce water and acetate ions, making the solution only slightly more basic. Conversely, adding a strong acid introduces H+ ions, which react with acetate ions to form acetic acid, causing a negligible increase in acidity.
Buffers are most effective when they contain equal concentrations of an acid and its conjugate base. For instance, an acetic acid and sodium acetate buffer can effectively neutralize added strong acids or bases without significant changes in pH. This happens through ionization equilibrium shifts that neutralize added strong electrolytes, turning them into weak acids or bases.