A Strong Acid Like HCl

Question

A strong acid like HCl
A) ionizes completely in an aqueous solution.
B) increases the pH when added to an aqueous solution.
C) reacts with strong bases to create a buffered solution.
D) is a strong buffer at low pH.
E) both ionizes completely in aqueous solutions and is a strong buffer at low pH.

Accepted Answer

Strong acids ionize completely in aqueous solutions, meaning that all of the acid molecules dissociate into hydrogen ions (H+) and anions. This results in a very low pH and high acidity in the solution.

Answer: E
 A strong acid like HCl ionizes completely in aqueous solutions, as mentioned above. Additionally, at a low pH, an acidic solution can act as a strong buffer because it has a high concentration of hydrogen ions which can react with added base to maintain the pH at a relatively constant level. Therefore, both A and E are correct.