Quote:
Originally Posted by Bob148
Hey cali, is this a good place to remind you of my question from a while back?:
when acid dissolves into an aqueous solution and metal is introduced, a chemical reaction takes place. What does it look like on the micro scale?
I ask because I'm wondering what would happen if we could stop time and look at the reaction.
a) the H+ free proton will react with the loose electrons of the metal at a rate dependent on the molarity of the solution and the number of H+ cations per molecule released into the solution.
or?:
b) it's more wave like in nature and it's an electromagnetic mess which isn't as easily comprehended by humans.
or both?
It's complicated because you don't have homogeneous solutions of the metal. You have a solid metal surface with a coating of metal cations around it, the metal cation layer is sloughing off into solution exposing the metal.
Metals like Na and K react one electron at a time. So you may end up with H. (neutral hydrogen with one electron) which further reacts with H2O to give H2 and OH. (neutral radical species), etc.
The nature of the surface itself matters. The greater the surface area, the faster the metal reacts. If you have a big chunk it takes forever to react. Microscale crevices can greatly accelerate the reaction (the same way that Mentos accelerate the offgassing of Diet Coke).
These sorts of surface-solution reactions are very important in atmospheric chemistry. One of the huge breakthroughs in the field was when scientists discovered that small ice crystals floating in the polar atmospheres greatly accelerated the decomposition of ozone. That would probably be a good place to start Wikipediaing if this sounds interesting to you.