Dissolving 120 g of urca (mol . Wi 60) in 1000 gof water gave a solution of density `1.15` g/mL the molarity of the solution is

Options

A. `1.78` M
B. `2.00` M
C. `2.05` M
D. `2.22` M

Answer

C

Explanation

Nuber of moles of urea `= (120)/(60)=2`
Total mass of solution `=1000+120=1120g `
Total volume of solution (in L) `= ("Mass)/("Density") =(1120)/(1.15xx10^(3))=(112)/(115)l.`
Molarity of the solution `= ("Number of moles")/("Volume of solution litre")=(2xx115)/(112) =2.05 mol L ^(-1)`