What is the significance of solute concentration to osmosis?
Solute concentration is what we call osmotic pressure. Osmosis is water diffusing from an area of low osmotic pressure (low solute conc) to high osmotic pressure (high solute conc) through a semi-permeable membrane. This is because substances travel from where they have high concentration to where they have low concentration until equilibrium is reached. Where there are lots of solute molecules, there are less water molecules, so water will travel to this area.