Question

What makes a good buffer solution?

Answer 1

Buffer solution:

• “The solutions which resist change in pH on dilution or with the addition of small amounts of acid are called Buffer Solutions.”
• It is a mixture of a weak acid and its conjugate base or vice versa.

Characteristics of a good buffer solution:

• It should have a ${\mathrm{pK}}_{\mathrm{a}}$ between $6$ to $8$.
• It should be soluble in water.
• It should have minimal salt effects.
• It should have minimal effects on dissociation from changes in concentration and temperature.
• It should have well defined or nonexistent interactions with mineral cations.
• It should be chemically stable.
• It should not absorb UV light at the wavelengths used in photometric experiments.
• It should be easy to use and prepare.