What is the freezing point of a nonionizing antifreeze solution containing 388g ethylene glycol C_2H_6O_2C2H6O2 and 409 g of water?

1 Answer

The freezing point = - 28.42^oC28.42oC

Explanation:

∆T_b = i*K_f*m

  • ∆T_b = depression in freezing point
  • i = vant hoff factor
  • K_f = depression constant
  • m = molality

mass of ethylene = 388 g

molar mass = 62.07 g/mol

no. of moles = 388/62.07 = 6.25 moles

mass of solvent = 409 g = 0.409 kg

molality = 6.25 moles/0.409 kg = 15.28 m

  • i = 1

  • T_i = 0^oC

  • K_f= 1.86^ oC/m

Therefore,

∆T_f = i*K_f*m
∆T_f = 1.86^oC/m xx 15.28 m

∆T_f = 28.42^o C

T_f = 0^oC - 28.42^ oC = -28.42^ oC