The van 't Hoff factor, is the number of molecules of solute actually in solution, per molecule of solid solute added. Equivalently, I refers to the ratio of true molecular mass to calculated molecular methods by colligative methods. It is named after Jacobus Henricus van 't Hoff , the first winner of the Nobel Chemistry prize
The van 't Hoff factor is important in quantitative analysis of colligative properties, such as vapour pressure, and freezing point depression.
When solute particles associate in solution, I is less than unity. (Eg. Ethanoic acid in benzene, benzoic acid in benzene)
When solute particles dissociate in solution, I is greater than unity. (Eg. Sodium chloride in water, potassium chloride in water, magnesium chloride in water)
When solute particles neither dissociate nor associate in solution, I equals unity. (Eg. Glucose in water)
This is is short explanation of this factor that dominates chemistry practice.
The van 't Hoff factor is important in quantitative analysis of colligative properties, such as vapour pressure, and freezing point depression.
When solute particles associate in solution, I is less than unity. (Eg. Ethanoic acid in benzene, benzoic acid in benzene)
When solute particles dissociate in solution, I is greater than unity. (Eg. Sodium chloride in water, potassium chloride in water, magnesium chloride in water)
When solute particles neither dissociate nor associate in solution, I equals unity. (Eg. Glucose in water)
This is is short explanation of this factor that dominates chemistry practice.