Elevation of boiling point of 1 M KCl solution is nearly double thanthat of 1 M sugar solution.

The reason why the elevation of boiling point of 1 M KCl solution is nearly double than that of 1 M sugar solution is due to the difference in the number of particles that each solution produces in solution.

Here are the steps to understand this:

1. Boiling point elevation is a colligative property, which means it depends on the number of solute particles in a solution, not on the type of particles.

2. When sugar (sucrose, C12H22O11) dissolves in water, each sugar molecule stays as a single particle. So, 1 mole of sugar in solution produces 1 mole of particles.

3. However, when KCl dissolves in water, it dissociates into two ions, K+ and Cl-. So, 1 mole of KCl in solution produces 2 moles of particles.

4. Because the number of particles affects the boiling point elevation, and KCl produces twice as many particles as sugar, the boiling point of a 1 M KCl solution is nearly double that of a 1 M sugar solution.