Question

An aqueous solution of urea containing 18 g urea in 1500 `cm^(3)` of solution has a density of 1.5 `g//cm^(3)` . If the molecular weight of urea is 60. Then the molality of solution is:
A. `0.200`
B. `0.192`
C. `0.100`
D. `1.200`

Answer 1

Correct Answer - B
`1500 c c" solution"=1500xx1.052g=1578g`
Weight of solvent = 1560g,
Weight of solute = 18g
Molality
`=("Weight of solute")/("Molecular weight of solute "xx" weight of solvent in kg")`
`=(18xx1000)/(60xx1560)=0.192m`