The van't Hoff factor for KCl is i= 1.85. What is the boiling point of a 0.50 m solution of KCl in water? For water, Kb = 0.51. I have the equation which i beleive is (Delta Tb)= Kb x m x i ?? m= molality.... = .50 m Kb is given 0.51 i is given 1.85 I have to have 5 sig figs and the answer i get is .47175, but that's not right supposedly. What I'm I doing wrong?