Question

The mole fraction of methanol in its 4.5 molal acqueous solution is
A. `0.250`
B. `0.125`
C. `0.100`
D. `0.075`

Answer 1

Correct Answer - B
No. of moles of methanol in 1000 g water = 4.5
No. of moles of water in 1000 g of water
`(1000)/(18)=55.5`
Mole fraction of methanol `=(4.5)/(4.5+55.5)`
=0.075