Benzoic acid is dissolved in benzene, van’t Hoff factor will be

When benzoic acid dissolve in benzene it will be dimerise due to the intermolecular hydrogen bonding

${\text{2\hspace{0.17em}C}}_{\text{6}}{\text{H}}_{\text{5}}\text{COOH}\underset{ }{\overset{\text{Benzene}}{\to }}{\left({\text{C}}_{\text{6}}{\text{H}}_{\text{5}}\text{COOH}\right)}_{\text{2}}$