Chapter 16 - Ionic Equilibrium

Buffer solution

A solution that resists changes in pH upon the addition of small amounts of acid or base. It contains components that act as both an acid and a base, neutralizing the added acid or base.

Acidic buffer

A buffer made by mixing a weak acid and its conjugate base.

Basic buffer

A buffer made by mixing a weak base and its conjugate acid.

Henderson-Hasselbalch equation

An equation used to calculate the pH of a buffer solution based on the pKa and initial concentrations of the weak acid and salt of the conjugate base.

Buffer capacity

The amount of acid or base a buffer can absorb without significant changes in pH. It is determined by the concentrations of buffering components.

Buffer range

The pH range in which a buffer is effective. It is typically pKa ± 1.

Titration curve

A graph that represents the pH of a solution versus the volume of added titrant during a titration.

Equivalence point

The point in a titration when enough titrant has been added to react exactly with the substance being titrated. The moles of acid and base are stoichiometrically equal at this point.

Endpoint

The point in a titration when the indicator changes color, indicating the completion of the reaction.

pH curve

A graph that represents the progress of a titration by plotting the pH of the solution versus the volume of added titrant.