What is the pH of a solution prepared by mixing 10.0 mL of a strong acid solution with pH = 2.0 and 10.0 mL of a strong acid solution with pH = 6.0
A) 2.0
B) 2.3
C) 4.0
D) 6.0
E) 8.0

Question

Quizplus · Accepted Answer

To calculate the pH of the solution, we need to use the formula:

pH = -log[H+]

where [H+] is the concentration of hydrogen ions in the solution.

For the first solution with pH = 2.0, we have:

pH = -log[H+]
2 = -log[H+]
[H+] = 10^-2 M

For the second solution with pH = 6.0, we have:

pH = -log[H+]
6 = -log[H+]
[H+] = 10^-6 M

When we mix the two solutions together, the volumes add up to 20 mL. Therefore, we can calculate the new concentration of hydrogen ions as follows:

[H+] = (10 mL * 10^-2 M + 10 mL * 10^-6 M) / 20 mL
[H+] = 5.5 * 10^-3 M

Finally, we can calculate the pH of the mixed solution as:

pH = -log[H+]
pH = -log[5.5 * 10^-3]
pH = 2.3

Therefore, the answer is B.

What Is the PH of a Solution Prepared by Mixing