Dissolving `120g` of urea (mol wt `= 60)` in 1000g of water gave a solution of density 1.15 g/mL. The molarity of the solution is

Options

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

Answer

C

Explanation

`"Molarity"=("Number of moles of solute")/("Volume of solution (L)")`
`"Number of molesof urea"=(120)/(60)=2`
Weight of solution = weight of solvent + weught of solute
`=1000+120=1120g`
`rArr"Volume"=(1120g)/(1.15g//mL)xx(1)/(1000mL//L)=0.974L`
`rArr"Molarity"=(2.000)/(0.974)=2.05M`