5 Questions
What happens to a buffer solution when a strong base is added?
The solution is protected by the acid CH3COOH
What happens to a buffer solution when a strong acid is added?
The solution is protected by acetate (CH3COO-)
What does acetate (CH3COO-) do when strong base (OH-) is added to a buffer solution?
Converts excess protons and uses them to manufacture more weak acid, preventing large increase in pH
What is the molar ratio, [Salt]/[Acid], required to prepare an acetate buffer of pH 5.0?
[Salt]/[Acid] = 1.58, 61.5% salt
What is the pH of a solution containing 0.10 mole of ephedrine and 0.01 mole of ephedrine hydrochloride per liter of solution?
pH = 5.12
Study Notes
Buffers
- A buffer is a compound or mixture of compounds that resists changes in pH when small amounts of strong acid or base are added to a solution.
- Buffers can be a combination of a weak acid and its conjugate base (e.g., HAc and NaAc) or a weak base and its conjugate acid (e.g., Ephedrine and Ephedrine HCl or NH3 and NH4Cl).
Buffer Action
- Buffer action is the resistance of a buffer to changes in pH.
- When a small amount of strong acid or base is added to water or a solution of sodium chloride, the pH changes significantly, demonstrating a lack of buffer action.
Buffer Capacity (β)
- Buffer capacity (β) measures the magnitude of a buffer's resistance to pH changes.
- High buffer capacity is necessary to maintain a constant pH, such as in blood, which is maintained at pH 7.4.
Importance of Buffers
- Buffers are frequently used in pharmaceutical practice to hold the pH constant, particularly in ophthalmic and I.V. injections.
- The ability of a buffer to resist changes in pH is crucial in these applications.
Test your knowledge of buffer solutions with this quiz. Learn about the compounds that resist changes in pH and their importance in maintaining stable pH levels in solutions.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
