Question

Stomach acid has a pH of approximately 2. Sour milk has a pH of 6. Stomach acid is

• A. 3 times as acidic as sour milk
• B. 4 times as acidic as sour milk
• C. 100 times as acidic as sour milk
• D. 10,000 times as acidic as sour milk

Hint:

For each 1 unit decrease in pH, the acidity increases by a factor of 10.

Answer 1

The Correct Option is D

The pH scale is logarithmic, meaning a change of 1 pH unit represents a tenfold change in acidity. The difference in pH between stomach acid (pH 2) and sour milk (pH 6) is 4 pH units. Therefore, stomach acid is 10\(^4\) (or 10,000) times more acidic than sour milk. Thus, the correct answer is (d).