Question

What is the approximate $pH$ of $1\times 10^{-3}MNaOH$ solution?

• A. 3
• B. 11
• C. 7
• D. $1\times 10^{-11}$

Answer 1

Answer: (B)

Given $\left[O{H}^{-}\right]=10^{-3}$
$\therefore pOH=3$
$\because pH+pOH=14$
$\therefore pH=14-3=11$