When an electrolyte is dissociated in solution, the van 't Hoff factor (i) is,
If a fraction α of the solute dissociates into n ions, then i=αn+(1−α)=1+α(n−1) So i>1 for electrolytes that dissociate in solution
The degree of dissociation (α) of a weak electrolyte, AxBy is related to van ’t Hoff factor (i), by the expression: