Question

Solution A has a pH of 2. Solution B has a pH of 4. Which is true?

A. [H+] in solution A is twice the [H+] in solution B.
B. [H+] in solution B is twice the [H+] in solution A.
C. [H+] in solution A is 100 times the [H+] in solution B.
D. [H+] in solution B is 100 times the [H+] in solution A.

Answer 1

Solution A has a pH of 2, which is 100 times the [H+] concentration of Solution B with a pH of 4, because each unit change in pH represents a tenfold difference in [H+].

Step-by-step explanation:

The pH scale is logarithmic, meaning each whole number on the scale represents a tenfold difference in hydrogen ion (H+) concentration.

When comparing Solution A with a pH of 2 and Solution B with a pH of 4, we see that for each step away from neutral (pH 7), the H+ concentration changes by a factor of 10.

Therefore, as Solution A has a pH that is two units lower than Solution B, it has a H+ concentration that is 10 times higher for each of those two units, leading to a total difference of 100 times.

The correct statement is: C. [H+] in solution A is 100 times the [H+] in solution B.