Answers

2016-03-12T09:26:25+05:30
ΔTF = KF *M*i
ΔTF - depression in freezing point
KF - molal cryoscopic constant
M - molality
i - Van't hoff factor

molecular weight of ethylene glycol - 62 g
31g of ethylene glycol = 31/62 mol
molality = (31/62) X (1000/500) = 0.25 mol/L
i=1
so, ΔTF = 0.25*1.86*1 = 0.465 

So freezing point of the solution is (273-0.465) =  272.535 K

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