Question

6.02 × 10²⁰ molecules of urea are present in 100 ml of its solution. The concentration of urea solution is(a) 0.02 M (b) 0.01 M (c) 0.001 M (d) 0.1 M(Avogadro constant, NA = 6.02 × 10²³ mol⁻¹)

Answer 1

If 6.022 x10^23 molecules are present in 1000 ml. of solution then concentration of the solution= 1M.

If 6.022 x 10^22 molecules are present in 100 ml.of the Solution, then the concentration of the solution= 1M.

If 6.022 x 10^20 molecules are present in 100 ml.of the solution, then the concentration of the solution= (6.022 x10^20/6.022 x 10^22) x 1 = 10^-2 x1 = 0.01 M .

The concentration of the Urea solution= 0.01M