Buffer Solutions and Henderson-Hasselbalch Equation Quiz

Buffer Solutions

• The ability of certain solutions to resist change in their pH upon addition of an acid or a base is called buffering capacity.

Buffer Equation

• The equation used to describe the relationship between a weak acid and its salt in a buffer solution is the Henderson-Hasselbalch equation.

Buffer Capacity

• The measure of the efficiency of a buffer in resisting changes in pH is buffer capacity (β).
• Buffer capacity (β) is expressed as the amount of strong acid or base that can be added to a buffer solution before its pH changes by one unit.

Maximum Buffer Capacity

• The maximum buffer capacity (β max) of a buffer solution containing a weak acid and its salt is when the concentrations of the acid and its conjugate base are equal.

Importance of Buffer Systems

• It is necessary to have a buffer system in some solutions to maintain a stable pH and prevent sudden changes in pH that could affect the solution or the system it is part of.

Expressing Buffer Capacity

• The conventional way to express the buffer capacity (β) of a solution is in terms of moles of acid or base per liter of solution per pH unit.

Buffering in Pharmaceuticals

• The primary purpose of buffering pharmaceutical solutions is to maintain a stable pH and ensure the stability and efficacy of the active ingredients.

Acidic Buffer

• An example of an acidic buffer is a solution of acetic acid and sodium acetate.

Mechanism of Action

• The mechanism of action of an acidic buffer when a strong base is added is that the base reacts with the weak acid to form its conjugate base, maintaining the pH.

Basic Buffer

• An example of a basic buffer is a solution of ammonia and ammonium chloride.

Phosphate Buffer

• The composition of a phosphate buffer is a solution of monobasic dihydrogen phosphate and dibasic monohydrogen phosphate.

Adding Strong Acid to Acidic Buffer

• When a strong acid is added to an acidic buffer, the acid reacts with the conjugate base of the weak acid, maintaining the pH.