Question

Calculate pOH of 0.001M HCl solution.

• A. \(11\)
• B. \(10\)
• C. \(12\)
• D. \(3\)

Hint:

HCl is a strong acid, so pH = 3 and pOH = 14 - 3.

Answer 1

The Correct Option is A

Step 1: Find hydroxide
Water gives $K_w = [\text{H}^+][\text{OH}^-] = 10^{-14}$. With $[\text{H}^+] = 10^{-3}$, $[\text{OH}^-] = 10^{-11}$ M.

Step 2: Take log
$\text{pOH} = -\log 10^{-11} = 11$.

Step 3: Result
Option (A). The value 3 in (D) is the pH.

Final Answer:
Option (A). \[ \boxed{11} \]