Diffusion - It is the movement of molecules from an area of High
concentration to an area of low concentration down a concentration
gradient. Basically the molecules go from where they are plenty of them
to where there are little.
Osmosis - Osmosis is basically the same thing as diffusion but it deals solely with water.Passage of a solvent
(such as water) from a lower-concentration solution to a
higher-concentration solution, through a semi-permeable membrane (that
allows the solvent to pass but not what is dissolved in it) separating the two solutions.......
Effusion - Effusion is when there is a barrier
with one or many small holes that prevent the gas to expand into the new
volume unless a gas molecule happens to travel through the hole. ..................