When a substance is added to a solvent, two processes take place: dissolving and dissociating. A solid substance is said to dissolve when it is equally distributed throughout a solvent to create a homogenous solution. The process by which a chemical separates into its constituent ions in a solution is referred to as dissociating, on the other hand.
The number of ions that a compound dissociates into when it is dissolved in a solvent is measured by the van't Hoff factor, also referred to as the ionization factor. For instance, the van't Hoff factor of table salt (NaCl), which dissociates into two ions in water (Na+ and Cl-), is 2. Contrarily, when sugar (sucrose) is dissolved in water, it does not separate into ions, hence its van't Hoff factor is 1.
The van't Hoff factor can typically be calculated experimentally by measuring the osmotic pressure or elevation of the solution's boiling point. A chemical that dissociates into ions in solution is indicated by a van't Hoff factor greater than 1, whereas a compound that does not disintegrate into ions is indicated by a van't Hoff factor equal to 1.