Buffers are substances that help resist shifts in pH by (From the close reading exercises) A. releasing H+ to a solution when acids are added.

B. donating H+ to a solution when bases are added.

C. accepting H+ from a solution when acids are added.

D. both donating H+ and accepting H+.

Buffers are substances that help resist shifts in pH by both donating H⁺ and accepting H⁺ (option D).

Explanation:

A buffer is a chemical substance capable of balancing the pH of a solution, when the balance is altered by the addition of an acid or a base. They are also called cushioning solution, and can be formed by an acid and its base conjugated, with a specific range of action.

The presence of a buffer in a solution has the ability to release hydrogen ions (H⁺) or accept them, helping to balance the pH, in the presence of a base or an acid, respectively. That is, a buffer can yield H⁺ to a solution when there are few or accept H⁺ when its content is high.

The other options are not correct because:

    A. Buffers do not release H+ into a solution when acids are added, but accept them.

     B and C.  Giving up H+ to a solution when bases are added or accepting H+ from a solution when acids are added are effects that buffers can potentially do, which is described in the text above.

they both go up but then go back down. they both end lower than they started. lastly, they both are competitive/the second on.

explanation: