The freezing point depression of 0.1 molal solution acid in benzene is 0.256 K. For benzene K_(f) is 5.12 K kg mol^(-1) Calculate the value of Van't Hoff factor for enzoic acid in benzene. What conclusion can you drow about the molecular state of benzonic acid in cenzene ?

The freezing point depression of 0.1 molal solution acid in benzene is

1.	The freezing point depression of 0.1 molal solution acid in benzene is 0.256 K. For benzene K_(f) is 5.12 K kg mol^(-1) Calculate the value of Van't Hoff factor for enzoic acid in benzene. What conclusion can you drow about the molecular state of benzonic acid in cenzene ?
Answer» SOLUTION :Step I. Calculation of Van't Hoff factor. `"Freezing point depression "(DeltaT_(f))=ixxK_(f)xxm` `DeltaT_(f)=0.256 K, K_(f)=5.12" K kg mol"^(-1),m=0.1m=(0.1" mol kg"^(-1))` `i=(DeltaT_(f))/(K_(f)xxm)=((0.256 K))/((5.12" K kg mol"^(-1))xx(0.1"mol"^(-1)kg))=0.5` Step II. Predicting the MOLECULAR state of benzoic acid. `i=("Normal MOLAR mass")/(Observed molar mass")=0.=1/2.` This shows that the observed molar mass of benzoni acid is double the normal molar mass or benzoic axists as a dimer in benzene.