Question

What is the pH of a solution if the concentration of \( \text{H}^+ \) ions is \( 1 \times 10^{-5} \, \text{mol/L} \)?

• A. 5
• B. 6
• C. 4
• D. 7

Hint:

Remember: pH is the negative logarithm of the hydrogen ion concentration. A pH of 7 is neutral, less than 7 is acidic, and greater than 7 is basic.

Answer 1

The Correct Option is A

Step 1: Use the formula for pH The pH of a solution is calculated using the formula: \[ \text{pH} = -\log[\text{H}^+] \] where \( [\text{H}^+] \) is the concentration of hydrogen ions in the solution. Step 2: Substitute the given concentration Given: - \( [\text{H}^+] = 1 \times 10^{-5} \, \text{mol/L} \). Substitute into the pH formula: \[ \text{pH} = -\log(1 \times 10^{-5}) = 5 \] Answer: Therefore, the pH of the solution is 5. So, the correct answer is option (1).