PLEASE HELP: What is the difference between osmosis and diffusion?

Diffusion is the movement of molecules or ions from a region of higher concentration to a region of lower concentration. When the distribution equalizes on both sides of a membrane, the process stops. There is no energy required for this process. Osmosis is the diffusion of water through a selectively permeable membrane.

Diffusion doesn’t have anything to do with any sort of membrane (semipermeable or otherwise). Diffusion is the movement of a solute (e.g., salt, sugar, dye) within a solvent (e.g., water or oil) from a region of higher concentration of solute to a region of lower concentration of solute until the solute is equally distributed within the solvent. For example, a teaspoon of salt added into a glass of water will eventually dissolve and diffuse, or spread evenly throughout the water in the glass - the salt won’t just sit in the bottom of the glass of water undissolved forever. For osmosis to occur, there has to be a membrane (e.g., a cell membrane, or your skin) that keeps the solute (e.g., salt) from passing through it but allows the solvent (e.g., water) through. Osmosis is the movement of water across a “semipermeable” or “selectively permeable” membrane from a region of low concentration of solute to a region of high solute concentration. For example, if you sit in a tub of fresh water long enough, your body (which contains salt) will begin to take on water. Most people believe that you shrivel in the tub but that is wrong: Your fingertips wrinkle because your fingertips are swelling with water, but because your skin is attached to the deeper flesh in tiny patches (more so in some spots than in others), the uneven swelling looks like wrinkles. The osmosis continues until the concentration of salt in the water is the same on both sides of the membrane, even if that means that all the water is drawn through the membrane to the side of the membrane with the most salt.

osmosis:-diffusion of solvent (water) through a membrane from low solute concentration to high solute concentration . diffusion:- transport of molecules from higher concentration to lower concentration.