Question

What is diffusion? Explain.

Answer 1

Concentration gradient is the process by which particles, which are sometimes called solutes, moves through a solution or gas from an area of higher number of particles to an area of lower number of particles, the actual movement is called diffusion.
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Answer 2

The process of free movement of molecules of a substance (such as gas, liquid and solid) from a region of higher concentration area to a region of lower concentration area when the two are in direct contact is called diffusion. 

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