Answer to Question #157846 in General Chemistry for anissa

Question

100cm³ of 0.20 mol/dm³ K₂SO₄ are added to 100cm³ of water and mixed thoroughly. What is the molarity of K⁺ ions in the resulting solution.

Answer 1

Initial Volume(V1) = 100 cm³ = 100/1000 = 0.10 dm³

Final Volume (V2) = 100 +100 = 200 cm³ = 200/1000 = 0.20 dm³

initial concentration of K₂SO₄ (M1)= 0.20 mol/dm³

Now, Using dilution law,

M₁V₁ = M₂V₂

0.10 × 0.10 = M₂× 0.20

M₂ = 0.10 × 0.10 /0.20

= 0.050 mol/dm³

Now, concentration of K⁺ = 2×0.050 = 0.10 mol/dm³