Molarity/molality help #2

Question

How many moles of NaOH are contained in 68.5 mL of a 2.10 M solution of NaOH in H₂O?

__ mol

Answer 1

To find the answer of the moles of NaOH we need to remember that M=moles/L. Since we are given the molarity and the volume we have all the information we need to solve for moles as follows:

68.5 mL=0.0685L

moles=M*L=2.10M*0.0685L=0.14385 moles

With sig figs this should give us 0.144 moles NaOH