No, it isn't correct although I suspect you worked it correctly. I suspect you simply read your calculator incorrectly.
mL x M = mL x M (you can use this simplified expression since the reaction is 1:1 and ONLY then).
20 x 0.01 = 30 x M
M = (20*0.01)/30 = 0.00667 which rounds to 0.0067 M.
If your calculator is like most, you have it set to read to two places, so the calculator rounds 0.006 to 0.01.
If 20 mL of 0.01 M aqueous HCl is required to neutralize 30 mL of an aqueous solution of NaOH, determine the molarity of the NaOH solution.
==> I got 0.01 M NaOH as my answer. Is this correct?
2 answers
Ohhh I see. This makes more sense. Thank you! :)