Question

Which of the following is true for a buffered solution?

The solution resists any change in its [OH-].
The solution will not change its pH very much even if a concentrated acid is added.
The solution resists any change in its [H+].
All of the the statements are true.*
The solution will not change its pH very much even if a strong base is added.

Answer 1

I agree with some reservations about addition of strong acid or strong base. A buffered solution CAN be overwhelmed wbut with moderate amounts of strong acid or strong base I agree.

Answer 2

If one titrates a buffered solution and a non-buffered solution where both have the same concentration of weak electrolyte (wk acid or wk base), both would have the same equivalence point. The difference is on addition of titrant (e.g., NaOH into HOAc/OAc Buffer vs NaOH into HOAc) the buffered system would demonstrate very little change in pH en-route to the equivalence point whereas the non-buffered system would start at a lower pH (i.e., acidic soln) and demonstrate a much higher pH change for the same amount of titrant added.