A buffer resists changes in the concentration of which ions?

Rationale

Hydrogen ions (H) are the ones whose concentration changes are resisted by a buffer.

Buffers are chemical solutions that help maintain a constant pH level in a solution. They do this by moderating the levels of hydrogen ions (H+) and hydroxide ions (OH-) when acids or bases are added to the solution.

A (Sodium (Na+)) YOUR ANSWER

Hydrogen ions (H+) are directly involved in the definition of pH, which is the negative logarithm of the hydrogen ion concentration. Buffers work by absorbing excess H+ ions when an acid is added and releasing H+ ions when a base is added, effectively resisting a change in pH. Therefore, the concentration of hydrogen ions is the one that a buffer resists changes in.

B (Hydroxide (OH-)) YOUR ANSWER

Sodium ions (Na+) are not involved in pH regulation. While they are important for functions like nerve transmission and muscle contraction, they do not directly affect the pH of a solution. Therefore, buffers do not resist changes in the concentration of sodium ions.

C (Hydrogen (H+)) CORRECT

While hydroxide ions (OH-) are involved in pH regulation, buffers primarily resist changes in hydrogen ion concentration. This is because pH is defined by the concentration of hydrogen ions. However, it's worth noting that a buffer can indirectly control OH- concentration via Le Chatelier's principle, as OH- and H+ concentrations are inversely related.

D (Potassium (K+)) YOUR ANSWER

Potassium ions (K+) are crucial for cellular functions like maintaining membrane potential, but they do not directly influence the pH of a solution. Thus, buffers do not resist changes in the concentration of potassium ions.

Conclusion

Buffers are critical in maintaining the pH of a solution by resisting changes in the concentration of hydrogen ions (H+). This is done by absorbing excess H+ ions when an acid is added and releasing H+ ions when a base is added. While sodium (Na+) and potassium (K+) ions are important for other biological functions, and hydroxide ions (OH-) are involved in pH regulation, it is the concentration of hydrogen ions that a buffer primarily resists changes in.

A buffer resists changes in the concentration of which ions?

Hydrogen ions (H) are the ones whose concentration changes are resisted by a buffer.

Related Questions

Related Quizzes

How familiar were you with this question?

Report an Issue

Rate this Practice Test