1.

A solutionn of urea in water has a boiling point of 100.18^(@)C. Calculate the freezing point of the same direction.Molal constants for water K_(f) and K_(b) are 1.86 and 0.512 respectively.

Answer»

Solution :For a solution of molality m we have
`m=(DeltaT_(F))/(K_(f))=(DeltaT_(b))/(K_(b))`…………..(Eqns 7 and 8 )
`:.DeltaT_(f)=DeltaT_(b).(K_(f))/(K_(b))`, `(DeltaT_(b)=100.18-100=0.18^(@))`
`=0.18xx(1.86)/(0.512)=0.654^(@)`
As the f.p. of PURE WATER is `0^(@)C`, the f.p. of the solution will be `-0.654^(@)C`


Discussion

No Comment Found

Related InterviewSolutions