Question

(3) How much volume of water need to be added
to 50 ml 0.1 M NaOH to make its
concentration 0.01 M?
(A) 450 ml
(B) 500 ml
(C) 50 ml
(D) 100 ml​

Answer 1

Molarity (M) : The number of moles of a solute dissolved in 1 L (1000 ml) of the solution is known as the molarity of the solution.

Molarity of a solution

(M)=

molar mass of solute

mass of solute

×

volume of solution in mL

1000

∴0.2=

40

w

×

500

1000

so w=4gm.

Amount of sodium hydroxide present in 500ml of 0.2M solutions is 4 gm.