  A solute-blocking model is presented that provides a kinetic explanation of
osmosis and ideal solution thermodynamics. It validates a diffusive model of
osmosis that is distinct from the traditional convective flow model of osmosis.
Osmotic equilibrium occurs when the fraction of water molecules in solution
matches the fraction of pure water molecules that have enough energy to
overcome the pressure difference. Solute-blocking also provides a kinetic
explanation for why Raoult's law and the other colligative properties depend on
the mole fraction (but not the size) of the solute particles, resulting in a
novel kinetic explanation for the entropy of mixing and chemical potential of
ideal solutions. Some of its novel predictions have been confirmed, others can
be tested experimentally or by simulation.
