Ethylene glycol (molar mass = 62 g mol�1) is a common automobile antifreeze. calculate the freezing point of a solution containing 12.4g of this substance in 100 g of water. would it be advisable to keep this substance in the car radiator during summer? given : kf for water = 1.86k kg/mol kb for water = 0.512k kg/mol

Depression in any solute is known as the colligative property.

Here, ΔTf = kf*m m = molality which is equal to moles of solute per kg solvent

Moles of ethylene glycol = 12.4/62

Molality = 0.2/0.1=2

By substituting we get,

ΔTf = 1.86*2 = 3.72K

Difference in freeezing point = 3.72K ie Depression

Boiling point elevation = ΔTb = Kb*b*i

=0.512*2 = 1.024K

Boiling point of solution = 373+1.024= 374.024k= 101.024deg C

The boiling point increases with increase in ethylene glycol percentage.

The use of ethylene glycol increases boiling point and depresses the freezing point.

It act as a anti freezing agent also and can be keep this in car radiator during summer


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