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The molal depression constant of water is 1.86 K. Kg. mol-1. Calculate the depression in freezing point of 0.1 molal aqueous urea solution. |
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Answer» Depression in freezing point is given byΔT f =i×K f ×mΔT f =T fo −T f i= Vant hoff FACTOR =1 (for non electrolyte)K f =1.86K/mm= MolalityΔT f =i×K f × weight of solvent in kgmoles of solute Moles of SOLUTION (UREA) =0.02Molar mass of solute (urea) =60g/molWeight of solvent (water) =100g=0.1kg(T F0 −T f )=1×1.86× 0.1kg0.02 (0−T f ) o C=0.372T f =−0.372 o C |
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