Question

To what volume should you dilute 50.0ml of a 5.00M KI solution so that 25.0ml of the diluted solution contains 3.05g ok KI

Answer 1

Mass of KI = 3.05g

Molar mass of KI = 166g/mol

Moles of KI = mass/ molar mass = 3.05g /( 166g/mol) = 0.0184 mol

Volume of solution = 25 mL = 0.025 L

Molarity of KI (M₁) = moles/Volume = 0.0184 mol/  0.025 L = 0.735 M

Let volume to which given solution be diluted is V₁

Molarity of stock solution of KI (M₂) = 5.00 M

Volume of  stock solution of KI (V₂) = 50.0 mL = 0.050 L

NOw, M₁V₁ =M₂V₂

0.735 M * V₁ = 5.00 M * 0.050 L

V₁ = 0.340 L = 340 mL

Thus, the Volume to which  50.0ml of a 5.00M KI solution needs to be diluted is 340 mL

i.e. Add stock solution to a volumetric flask. and add water till the volume reach 340 mL