Question

The density of a solution prepared by dissolving 120 g of urea (mol. Mass=60 u) in 1000 g of water is 1.15 g/mL. The molarity if this solution is
A. `1.78 M`
B. `1.02 M`
C. `2.05 M`
D. `0.50 M`

Answer 1

Correct Answer - C
Weight of water = 1000 g
weight of solute (urea)=120 g
weight of solution =1000+120=1120g
Volume of solution `=("Mass")/("Density")=(1120)/(1.15)`
`=973.9 mL`
Molarity `=(120)/(60xx973.9)xx1000=2.05 M`