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Chemistry / Re: How to estimate time until concentration equilibrium?
« on: 25/08/2023 14:23:00 »OKHow big is your apparatus?Let's pretend that the apparatus is similar to what's shown here. Just replace the salt bridge with a tube, filled with a mixture of solutions from both containers.
And how far do you think the electrostatic effect of an ion's charge reaches before it is too small to influence things?
It's related to this
in water the species will be H3O+, H5O2+ and possibly some others( can't remember offhand).A fairly common model assumes that the species (in dilute solutions ) is H9O4 +
It's about a nanometre across.
It's obviously got a positive charge on it and it will attract the water molecules around it.
But that attraction isn't strong enough to overcome the forces arising from the random molecules in the liquid.
If it was then there would be more water molecules "stuck on" and you would have H11O5+ or H13O6+
So we know that the effective range of teh electrostatic forces on a H+ ion in solution in water is only about a nanometre.
So, once again; how big is your apparatus?
If it's more than a few nm you can pretty much ignore the direct electrostatic effects.
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