The first task you are assigned in your summer laboratory job is to prepare a concentrated NaOH stock solution. The molecular weight of NaOH is 40. How many grams of solid NaOH will you need to weigh out to obtain a 500 mL solution that has a concentration of 10 M?
(a) 800 g
(b) 200 g
(c) 400 g
(d) 160 g
Answer: B