Question

A difference between diffusion and osmosis is :
a.) A semipermeable membrane is required for osmosis while diffusion requires no semi-permeable membrane.
b.) In osmosis movement of molecules is only in one direction whereas in diffusion movement is on both sides
c.) In osmosis only the solvent moves while in diffusion both solute and solvent move.
d.) None of the above.

Answer 1

Hint: Diffusion is the movement of any substance from a region of its higher concentration to a region of lower concentration. It occurs in all directions. Osmosis is the movement of water or any other solvent from a region of low solute concentration to a region of high solute concentration. It is a unidirectional phenomenon.

Complete step by step solution:
First, let’s see the difference between diffusion and osmosis.

DIFFUSION	OSMOSIS
It is the phenomenon of moving particles from a region of higher concentration to a region of lower concentration.	It is the phenomenon of moving solvent particles across a semipermeable from a region of low solute concentration to more solute concentration.
It occurs in liquids and gases.	It occurs in liquids only.
No membrane separation is required here.	It requires a semi-permeable membrane.
Water is not necessary for movement.	Water is the main solvent that moves from one region to another.
The flow of constituents is in all directions.	The flow of constituents occurs in one direction only.
Diffusion is a natural phenomenon that can not be stopped.	The process can be stopped or we can reverse it by applying an external force.
All the types of substances present in the solution can move from the region of its high concentration to the region of low concentration.	There is a movement of only water or any other substance from a region of higher concentration of solvent to the region of low concentration.
Example – Addition of ink in water leads to the colouring of the water.	Example – Red blood cells swell up when exposed to water.

Now, after studying all the differences between osmosis and diffusion; we can conclude that options a.), b.) and c.) all three are the correct answers.

Note: Diffusion does not require a semipermeable membrane while osmosis does require. When osmosis is a unidirectional phenomenon; the diffusion occurs in all directions. Further, in osmosis, the only solvent flows while in diffusion, all constituents move.