Answer to Question #297919 in General Chemistry for Phia

Question

You add 1 kg of ethylene glycol (C2H6O2) antifreeze to 4500g of H2O in your car’s radiator. What would be the freezing point of the solution?

Answer 1

Mass of C2H6O2= 1kg= 1000g

Molar mass of C2H6O2= 62.08g/mol

Mass of H2O = 4500g = 4.5kg

Kf of H2O = -1.86 °c/m

1000g × 1/62.08 = 16.108 mol C2H6O2

16.108 mol ÷ 4.5 kg H2O = 3.58 m C2H6O2

Change of Tf = Kf × m = (-1.86×3.58)

= -6.659°C

Freezing point of the solution:

= -6.659°C