Question

Use the scenario to answer the following question. A group of students working in a chemistry lab are planning a procedure to neutralize 10.0mL of 5.0 M hydrochloric acid (strong acid) with 5.0 M potassium hydroxide (strong base). In their procedure they plan on adding an equal volume of the base to the acid. What would be the expected outcome of carrying out this step as planned?

a- The resulting pH will be less than 7 because potassium hydroxide is less concentrated than the hydrochloric acid.
b- The resulting pH will not be able to be determined because the concentrations of the acid and base are not the same.
c- The resulting pH will be greater than 7 because potassium hydroxide is less concentrated than the hydrochloric acid.
d- The resulting pH will be equal to 7 because a strong base will neutralize a strong acid.

Answer 1

d- The resulting pH will be equal to 7 because a strong base will neutralize a strong acid.

Step-by-step explanation:

The reaction between potassium hydroxide and hydrochloric acid of equal volume and equal concentration yields a solution of pH 7 at equivalence point. We must note that KOH is a strong base while HCl is a strong acid. This fact influences the pH of the system at equivalence point.

Owing to the fact that the acid is exactly neutralized by the base; at the equivalence point of such titration, it is expected that hydrogen ions(H+) and hydroxide ions (OH-) must have reacted to form water, this leads to a final pH of 7.