30 g of urea (M=60g `mol^(-1)`) is dissolved in 846g of water. Calculate the vapour pressure of water for this solution if vapour pressure of pure water at 298 K is 23.8 mm Hg.
(b) Write two differences between ideal solutions and non-ideal solutions,

Answer

`23.55 mm`

Explanation

`(p^(@)-p_(s))/(p^(@))=(n_(2))/(n_(1))=(w_(2)//M_(2))/(w_(1)//M_(1))" (solution is taken as dilute as it is less then 5%)"`
`(23.8-p_(s))/(23.8)=(30//60)/(846//18)" or "p_(s)=23.55mm`