J.R. S. answered • 02/02/20

Ph.D. University Professor with 10+ years Tutoring Experience

ΔT = imK

ΔT = change in temp = ?

i = vant Hoff factor = 1 for ethylene glycol a non electrolyte

m = molality = mol/kg solvent = 400.0g x1 mol/62g /0.6 kg = 10.8 m

K = freezing constant = 1.86

ΔT = (1)(10.8)(1.86) = 20 degrees

New freezings point is -20 degrees C

You arent wrong. The answer sheet is incorrect. If the question asked for the freezing point DEPRESSION, the B would be the answer. But since it asks for th new freezing point, D is the answer.