A solution of urea (molar mass 60 g mol - 1 ) boils at 100 . 20 ° C at the atmospheric pressure. if K f and K b for water are 1 . 86 and 0 . 512 KKgmol - 1 respectively. The freezing point of the solution will be

Step-by-step solution

We know that whenever a non-volatile solute is added to a liquid solvent a boiling point of solution rises while there is a depression in the freezing point of the solution. Now, ∆ T b   =   K b m ∆ T b   =   100 . 20 - 100   =   0 . 20 °   C So, molality of solution will be Molality = 0 . 20 1 . 86   m Thus, for freezing temperature ∆ T f   =   K f × m ∆ T f   =   1 . 86 × 0 . 20 1 . 86 ∆ T f   =   0