A buffer is a solution that resists significant changes in pH when small amounts of acid or base are added. It typically consists of a weak acid and its conjugate base, or a weak base and its conjugate acid.
5 Must Know Facts For Your Next Test
Buffers maintain pH stability by neutralizing added acids (H+ ions) or bases (OH- ions).
The Henderson-Hasselbalch equation, $pH = pK_a + \log \left( \frac{[A^-]}{[HA]} \right)$, is used to calculate the pH of buffer solutions.
Buffers are most effective when the pH is close to the $pK_a$ value of the weak acid in the solution.
Biological systems heavily rely on buffers; for example, human blood maintains its pH around 7.4 using bicarbonate buffering.
Buffer capacity depends on the concentrations of the buffering agents; higher concentrations provide greater resistance to pH change.
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Related terms
Conjugate Acid-Base Pair: A pair consisting of an acid and its corresponding base, differing by a single proton ($H^+$).
$pK_a$: The negative logarithm of the acid dissociation constant ($K_a$), representing an acid's strength.