How many ml of .050 M NaOH are required to prepare 1500.0 mL of .0020 M NaOH? Please show work, I'm not sure how to do this. Thanks!

2 answers

How many moles are in the solution you want to prepare? M x L = moles. So you must add that many moles of the more concentrated solution. L x M = moles again. You know M and you know moles (from the first calculation), solve for L.
Or you can always take the easy way out.
mL x M = mL x M. Plug and chug.
mL x 0.05 = 1500 x 0.002
Solve for mL of the 0.05 M soln.