Thanks for the question!

It is definitely a very interesting question to solve and do some brainstorming.

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Diffusion is the tendency in the variety part if molecules, atoms, ions, etc., of various media of gases, solids and LIQUIDS to get evenly and equally distributed throughout the availability of space on the special account applied called their random kinetic motion of PARTICLES in a given container or medium or in a membrane for free FLOWING by random kinetic motion of particles due to the kinetic allowance of energy present on the particulate motion.

Or, Diffusion can also be, by the presence of a membrane involving movement of substances for exchanging the molecules in the form of particles from the region of higher concentration, freely available energy or Diffusion pressure exerted to the region of a lower concentration, by freely available energy and Diffusion pressure exerted through a container or membrane.

Some of the diffusive particles or those which are scattered easily or bombarded on them by a semi-permeable or permeable membranes which are fully allowed to enter wide range molecules, but, are not allowed to pass through by selective permeable membranes and which does not allow any flow of any molecules (fully permeable). These Diffusion-Able particles are Water, Carbon dioxide, Oxygen, Nitrogen, Hydrogen (have a greater availability for diffusing more rapidly into available container containing permeable membranes) which are few of the simple molecules making an allowance for gaseous exchange. Others which are not required, but, still make an exception are rather deemed or is harmful or not harmful, such as, carbon monoxide, methylene BLUE or methylthioninium chloride (used for treatments and specially oxygen therapy), methyl-propan-3-one-2-carboxylate or Methyl beta-phenylglycidate, Perindopril erbumine, Propane-1,2,3-tricarboxylic acid, etc. are some substances which can readily induce into a cell membrane when it is semi-permeable or not permeable at all.


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Hope it helps and SOLVES your query!!