Question

What is the pH of a solution with a hydrogen ion concentration of \( [H^+] = 1 \times 10^{-4} \, \text{M} \)?

• A. 4
• B. 7
• C. 10
• D. 3

Hint:

The pH scale is logarithmic, where a decrease in \( [H^+] \) by a factor of 10 corresponds to an increase in pH by 1 unit.

Answer 1

The Correct Option is A

The pH of a solution is given by the formula: \[ \text{pH} = -\log[H^+] \] Substituting the given hydrogen ion concentration \( [H^+] = 1 \times 10^{-4} \, \text{M} \): \[ \text{pH} = -\log(1 \times 10^{-4}) = 4 \] Thus, the pH of the solution is 4.