Question

What is the pH of a 0.01 M hydrochloric acid (HCl) solution?

• A. 1
• B. 2
• C. 3
• D. 4

Hint:

For strong acids like HCl, the concentration of \(\text{H}^+\) is equal to the concentration of the acid.

Answer 1

The Correct Option is B

We are given a 0.01 M solution of hydrochloric acid (HCl). Hydrochloric acid is a strong acid, which means it dissociates completely in water. Step 1: Write the dissociation equation \[ \text{HCl} \to \text{H}^+ + \text{Cl}^- \] Since HCl is a strong acid, the concentration of hydrogen ions (\(\text{H}^+\)) is equal to the concentration of HCl, which is 0.01 M. Step 2: Calculate the pH The formula for pH is: \[ \text{pH} = -\log[\text{H}^+] \] Substituting the concentration of hydrogen ions: \[ \text{pH} = -\log(0.01) = -\log(10^{-2}) = 2 \] Answer: The pH of the solution is 2, so the correct answer is option (2).