what is the total # of grams of NaOH(formula mass=40) needed to make 1.0 liter of a 0.20 M solution

a. 80.g
b. 2.0g
c. 8.0g
d. 20.g

Go back to the molarity definition.

is the answer b

molarity = #mols/L
0.20 M means we want # mols in 1 L to be 0.20 mols. grams = mols x molar mass = 0.2 x 40 = ??

C?

0.20 x 40 = 8.0g