Question

a. (3 pts) All Brønsted-Lowry acids contain the hydrogen ion, H+ . True False

b. (3 pts) You can use any acid/conjugate base pair in making a buffer. True False

c. (3 pts) Concentration does not matter for acids/conjugate bases in buffers. True False

Answer 1

a. All Bronsted-Lowry acids contain the H+ ion. True.

Explanation: A Bronsted-Lowry acid is a chemical species that donates one or more hydrogen ions in a reaction. In contrast, a Bronsted-Lowry base accepts hydrogen ions. When it donates its proton, the acid becomes its conjugate base. A more general look at the theory is an acid as a proton donor and a base as a proton acceptor.

b. False.

Explanation: A buffer is an aqueous solution consisting of a mixture of a weak acid and its conjugate base or a weak base and its conjugate acid. ​Hence any acid/conjugate base can't be used. It must be weak acid and it's conjugate base.

c. False. As concentration of acid and conjugate base determine the effectiveness of the buffer i.e., buffer capacity depends on the concentration.

Explanation:

The goal of a buffer is to keep the pH of a solution within a narrow range. While the ratio of [A^-]/[HA] influences the pH of a solution, the actual concentrations of A^- and HA influence the effectiveness of a buffer.The more A^- and HA molecules available, the less of an effect addition of a strong acid or base will have on the pH of a system.