* Buffer Definition: A buffer solution resists changes in pH when small amounts of acid or base are added. It consists of a weak acid and its conjugate base (or a weak base and its conjugate acid).
* Acetic Acid and Acetate Ion:
* HC₂H₃O₂ (acetic acid) is a weak acid.
* C₂H₃O₂⁻ (acetate ion) is its conjugate base.
* How the Buffer Works:
* When a strong acid is added, the acetate ions (C₂H₃O₂⁻) react with the added H⁺ ions to form more acetic acid, minimizing the pH change.
* When a strong base is added, the acetic acid (HC₂H₃O₂) reacts with the added OH⁻ ions to form water and acetate ions, again minimizing the pH change.
Therefore, the presence of both the weak acid (HC₂H₃O₂) and its conjugate base (C₂H₃O₂⁻) in the solution allows it to act as a buffer.
