When the acetic acid / sodium acetate buffer is titrated with NaOH, some of the acetic acid is consumed according to the reaction: CH₃COOH + ^-OH CH₃COO^- + H₂O

(Note that the sodium is omitted, as a spectator ion it does not participate in any of the chemical reactions.)

What chemical reaction occurs after the reaction above to stabilize the pH of the solution in the beaker beneath the buret?

1. CH₃COO^- + H₃O⁺ CH₃COOH + H₂O
2. CH₃COO^- + H₂O CH₃COOH + ^-OH
3. CH₃COO^- + CH₃COOH CH₃COO--H⁺--OOCCH₃
4. two of these
5. all of these

When the ammonia / ammonium chloride buffer is titrated with HCl, some of the ammonia is consumed according to the reaction: NH₃ + H₃O⁺ NH₄⁺ + H₂O

(Note that H₃O⁺ is used in place of HCl. HCl dissociates completely in water and the lone H⁺ quickly reacts with H₂O to form H₃O⁺. Chloride is omitted because it is a spectator ion.)

What chemical reaction occurs after the reaction above to stabilize the pH of the solution in the beaker beneath the buret?

1. NH₄⁺ + H₂O NH₃ + H₃O⁺
2. NH₄⁺ + -OH NH₃ + H₂O
3. NH₄⁺ + -OH NH₄OH
4. two of these
5. all of these

Hello, I can't seem to figure out these, and I would greatly appreciate an answer with a little explanation that could help me with future problems such as these, thank you!