ATI TEAS (Test of Essential Academic Skills) Version 7ScienceMedium
A technician is preparing a solution of a weak acid and its conjugate base to maintain a stable pH for a biochemical reaction. This type of solution is known as a:
- ABuffer solution
- BSaturated solution
- CSuspension
- DColloid
Show answer & explanationAnswer & explanation
Correct answer: A. Buffer solution
A buffer solution is specifically designed to resist changes in pH upon the addition of small amounts of acid or base. It typically consists of a weak acid and its conjugate base, or a weak base and its conjugate acid.
Why the other options are wrong
- B. A saturated solution contains the maximum amount of solute that can be dissolved at a given temperature, it does not inherently resist pH changes.
- C. A suspension is a heterogeneous mixture where solid particles are dispersed in a liquid and will eventually settle out; it is not related to pH stability.
- D. A colloid is a heterogeneous mixture with particles larger than a solution but smaller than a suspension, also not related to pH stability.
Buffer Solution
An aqueous solution consisting of a mixture of a weak acid and its conjugate base, or a weak base and its conjugate acid, that resists changes in pH upon the addition of small amounts of acid or base.
- Crucial for maintaining stable pH in biological systems and chemical reactions.
- Its buffering capacity is greatest near the pKa of the weak acid.
- Examples include bicarbonate buffer system in blood.
Memory trick: Buffers Balance pH.