Find the freezing point of a glucose solution whose osmotic pressure at `25^(@)C` is found to be 30 atm. `K_(f)` (water) `= 1.86 kg mol^(-1)K`.

Answer

`T_(f)=-2.28^(@)"C"`

Explanation

`"C"=(pi)/(RT)`
`"C"=(30)/(0.082xx298)`
In this problem we will assume:
`"Molality(m)=Molar concentration(c)"`
`"m"=(30)/(0.082xx298)`
`Delta"T"_("f")="K"_("f")"xm"=1.86xx(30)/(0.082xx298)`
`=2.28^(@)"C(app)"`
`"T"_("f")=0.00-2.28`
`"T"_("f")=-2.28^(@)"C"`