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Why are ionic reactions extremely fast, as compared to other gaseous reactions?

The ionic reactions (precipitations, neutralizations etc.) are extremely fast (somewhere about $10^{12}$ times faster) than gas-phase reactions and other ordinary reactions in solutions (inversion, substitution etc). Why is this so?

My thoughts
One possible reason might be the relative freedom of steric orientation in case of simple ionic reactions as compared to organic reactions and complicated gas reactions, but this isn't the case with simple gas reactions or formation and dissociation of ionic complexes, which do require specific steric orientations. The activation energy could be very low for ionic reactions, if this is so, then what is the reason behind it?

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Reaction rate is inversely proportional to activation energy for a given process. The examples given have very low barriers and often the diffusion in solution is the rate limiting process.

If you think of reaction of anion with cation, than there should be no barrier at all, because the interaction between oppositely charged species is strongly attractive.

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In ionic reactions there is no electronic transfer between ions and the number of collisions between ions with opposite charge in high.

When reaction occurs between neutral compounds, there is electronic transfer between atoms or molecules, and also there is bonding reorientation, son the speed in such reactions are lower than in ionic reactions.

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Reactions of ionic compounds are very fast because ionic compounds exist as ion in aqueous solutions.therefore no bond is to be broken.only few bonds are formed.EXAMPLE# by adding AgNO3 solution to NaCl solution,white ppt of AgCl are formed immediately.in this reaction,both AgNO3&NaCl are ionized.therefore no bond is broken,few are formed.thus reaction occurs rapidly

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  • $\begingroup$ This doesn't really add any new insight beyond what has already been said. $\endgroup$ – bon May 15 '16 at 20:54
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    $\begingroup$ It's not true - all those ions are solvated, particularly Ag+ $\endgroup$ – Mithoron May 15 '16 at 20:59

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