The boiling point of a solution is higher than that of the pure solvent due to the presence of solute particles in the solution. The solute particles interfere with the intermolecular forces between the solvent molecules, making it harder for them to escape from the liquid and turn into vapor. As a result, a higher temperature is required to reach the boiling point of the solution compared to the pure solvent.

The extent to which the boiling point is elevated depends on the concentration of the solution. The more concentrated the solution, the higher the boiling point. This is because there are more solute particles present to interfere with the intermolecular forces between the solvent molecules.

The boiling point elevation of a solution is a colligative property, which means that it depends only on the concentration of the solution and not on the identity of the solute particles. This is in contrast to properties such as boiling point and freezing point, which are affected by both the concentration and the identity of the solute particles.