Question

What will be the pH of an aqueous solution containing 0.040 mol/L sodium hydroxide??

I got 1.40 or 1.398 I rounded the numbers is
my answer right??? If not what's the right answer??

Answer 1

You calculated the pOH since it is 0.04M NaOH. YOu need to subtract your 1.40 from 14.00 for the pH.