Question

How many millilitres of water are necessary to add into 500 ml of 1M NaOH solution for preparing 0.2M solution?

Answer 1

Molar mass of NaOH (M) = 40 g mol-1

Volume of solution (V) = 250 mL

Molarity of NaOH solution = 2 M

Molarity = w×1000M×V

w (Mass of NaOH ) = 2×40×2501000 = 20 g

Hence , 20 g of NaOH will be required