Whats the difference between osmosis and diffusion?

Answer 1

In diffusion, molecules travel from a higher concentration to a lower concentration. When you put a drop of ink in a glass of water, the spreading of the ink in the water is called diffusion. Similarly, if you spray an air freshener in one corner of a room, eventually people on the other side of the room will be able to smell it as well because the scent has diffused.

In osmosis, molecules also travel from higher concentration to a lower concentration. However, osmosis specifically refers to the movement of WATER molecules. Both of these types of transport are examples of passive transport, which requires no energy.

Answer 2

The difference between diffusion and osmosis is that diffusion deals with the movement of molecules from an area of high solute concentration to an area of low solute concentration, while osmosis is the movement of molecules, in a similar fashion, across a semi-permeable membrane. See reverse osmosis.