What is diffusion? What is osmosis? …

Osmosis can be defined as the movement of water molecules from a higher water concentration area to the area of less water concentration through a semipermeable membrane. In other words, it can be defined as the diffusion of water molecules through a semipermeable membrane. It is a special case of diffusion of water (High to low). For example, water in the roots of plants is transported through osmosis.

Diffusion is the net movement of molecules of a substance from a region of their higher concentration to a region of their lower concentration. Net movement means there are more molecules moving in one direction than in the opposite direction.

Example: Opening a bottle of perfume in a room will result in the gradual diffusion of the perfume from the region of higher concentration (the bottle) out into the room. Diffusion will continue until the perfume has a more or less uniform concentration throughout the bottle and room.