Question

An aqueous urea solution is 5
molal. What is the mole fraction
of urea?​

Answer 1

Answer:

Mole fraction of urea in aqueous solution =0.05

0.05=

Moles of urea+

18

900

Moles of urea

0.05(Moles of urea)+2.5=Moles of urea

Moles of Urea=2.63 moles

Mass of urea =2.63×60=158 gm

Mass of solution =158+900=1058 gm

Density =1.2 g cm

3

Volume of solution =

1.2

1058

=881.67 ml

Molarity=

V

solution(innL)

n

solute

×1000

=

881.67

2.63

×1000

=2.9 ≃3 M