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Ethylene glycol is used as an antifreeze in a cold climate. Mass of ethylene glycol which should be added to 4 kg of water to prevent it from freezing at –6°C will be: (Kf for water = 1.86 Kg/mol and molar mass of ethylene glycol = 62 kg/mol)

Ethylene glycol is used as an antifreeze in a cold climate. Mass of ethylene glycol which should be added to 4 kg of water to prevent it from freezing at –6°C will be: (Kf for water = 1.86 Kg/mol and molar mass of ethylene glycol = 62 kg/mol) Correct Answer 804.32 g

∆Tf = kf.m 

for ethylene glycol in aq. solution

 ∆Tf = kf wmol.wt × 1000wt. of solvent6 = 1.86 x w x 100062 x 4000

=> w = 800 g

 

So, the weight of solute should be more than 800 g.

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