MCAT General Chemistry Question 137: Answer and Explanation

Home > MCAT Test > MCAT general chemistry practice tests

Test Information

Use your browser's back button to return to your test results.
Do more MCAT general chemistry practice tests.

Question: 137

2. Which of the following is closest to the pH of a solution containing 5 mM H₂SO₄?

A. 1
B. 2
C. 3
D. 4

Correct Answer: B

Explanation:

First, convert the concentration to 5 × 10^-3 M. Next, because sulfuric acid is a strong acid, we can assume that, for the majority of sulfuric acid molecules (although not all), both protons will dissociate. The concentration of hydrogen ions is therefore 2 × 5 × 10^-3, or 10^-2. The equation for pH is pH = -log [H⁺]. If [H⁺] = 10^-2 M, then pH = 2.

Previous Next