Question

What weight of glucose dissolved in 100 grams of water will produce the same lowering of vapour pressure as one gram of urea dissolved in `250 ` grams of water, at the same temperature ?
A. `3 g`
B. `5 g`
C. `6 g`
D. `4 g`

Answer 1

Correct Answer - 3
Since same lowering in vapour pressure.
`X_("solute of urea")=X_("solute of glucose")`
`((1)/(60))/((1)/(60)+(50)/(18))=((w)/(180))/((w)/(180)+(100)/(18))" "rArr" "((1)/(60))/((50)/(18))=((w)/(180))/((100)/(18))" "(` For dilute solution `)`
`rArr" "w=6` of glucose