Question

What is the pH of a solution with a hydrogen ion concentration of \( 1 \times 10^{-5} \, \text{mol/L} \)?

• A. 5
• B. 10
• C. 7
• D. 4

Hint:

Remember: pH is calculated using the formula \( \text{pH} = -\log[H^+] \), where \( [H^+] \) is the concentration of hydrogen ions.

Answer 1

The Correct Option is A

Given: \( [H^+] = 1 \times 10^{-5} \, \text{mol/L} \).

Step 1: Apply pH calculation The relationship between pH and hydrogen ion concentration is defined by: \[ \text{pH} = -\log[H^+] \] 

Step 2: Insert provided data Substituting \( [H^+] = 1 \times 10^{-5} \, \text{mol/L} \) yields: \[ \text{pH} = -\log(1 \times 10^{-5}) = 5 \] 

Answer: The calculated pH is 5, corresponding to option (1).