Question #b576d

1 Answer
Feb 4, 2017

The depression of freezing point of solvent DeltaT_f is related with the molality m of the solute as follows

color(blue)(DeltaT_f=-i*K_f*m..........[1])

where

K_f->"cryoscopic constant "=1.853Kkg"/mol for water"

m->"molality of the soute"=0.100

i->" van't hoff factor"=1+alpha

alpha->"degree of dissociation"=1.32%=0.0132

Replacing i by 1+alpha the equation [1] becomes

color(green)(DeltaT_f=-(1+alpha)*K_f*m)

color(green)(=>DeltaT_f=-(1+1.0132)*1.853*0.1K~~-0.188K)

So expected freezing point will be

color(red)("Expected freezing point"=(273-0.188)K=272.812K)