1.

Dissolving `120g` of urea `(Mw = 60)` in `1000 g` of water gave a solution of density `1.15 g mL^(-1)`. The molarity of solution is:A. `1.78 M`B. `1.02 M`C. `2.05 M`D. `0.50 M`

Answer» Correct Answer - C
Mass of solute =`120 g`
Molecular mass of solute `=60 u`
Mass of solvent `=1000 g`
Density of solution `=1.15 g//mL`
Total mass of solution `=1000+120=1120 g`
`"Volume of solution"=("Mass")/("Density")=(1120)/(1.15)mL`
`"Molarity"=(("Mass of solute")/("Molecular mass of solute"))/("Volume of solution")xx1000`
`=(120//60)/(1120//1.15)xx1000`
`=(2xx1000xx1.15)/(1120)=2.05 M`


Discussion

No Comment Found

Related InterviewSolutions