Question

Predict whether Van’t Hoff factor will be less or greater than one when Ethanoic acid is dissolved in benzene.

Hint:

Van’t Hoff factor (\(i\)) is less than 1 when solute molecules form complexes or dimers in solution.

Answer 1

Ethanoic acid (CH$_3$COOH) is a weak acid and it forms dimers in benzene due to hydrogen bonding between two molecules of ethanoic acid. The formation of dimers reduces the number of particles in the solution. Since Van’t Hoff factor \(i\) represents the number of particles in solution, for ethanoic acid in benzene, \( i \) will be less than 1 due to the dimerization process.
Step 1: Ethanoic acid dissociates into dimers, reducing the total number of particles in the solution.
Step 2: Therefore, the Van’t Hoff factor \( i \) will be less than 1.