How Solutions Form Without Energy Change

A solution can form as a spontaneous process. That means it happens under the right conditions without energy from an outside source. When the attraction between solute and solvent particles is about the same as the attraction in the separate substances, the solution forms with no energy change.

...

When two substances mix, the forces between the constituent molecules, or intermolecular forces, are disrupted.

Intermolecular forces can be of different types, such as dispersion forces between nitrogen molecules, dipole-dipole attractions between hydrochloric acid molecules, hydrogen bonding between ammonia molecules, and ion-dipole int...