Dissociation of solute molecules in solution refers to the process in which solute particles split into two or more simpler particles, usually ions, when dissolved in a solvent. This commonly occurs with electrolytes such as acids, bases, and salts in polar solvents like water.
For example, when sodium chloride (NaCl) dissolves in water, it dissociates into Na+ and Cl− ions:
\[\ce{NaCl_{(s)} -> Na{^+_{(aq)}} + Cl-_{(aq)}}\]This increases the number of solute particles in the solution, which in turn enhances colligative properties like osmotic pressure, boiling point elevation, and freezing point depression.
In such cases, the van’t Hoff factor (i) becomes greater than 1, indicating an increase in the number of particles due to dissociation.
