Question

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

• A. 5
• B. 6
• C. 4
• D. 7

Hint:

Remember: pH is calculated as \( \text{pH} = -\log[\text{H}^+] \). A lower concentration of \( \text{H}^+ \) ions corresponds to a higher pH.

Answer 1

The Correct Option is A

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