How do you achieve the exchange of reactants even though it is energetically less favourable?

Assuming that in a system the following pairs are energetically most favourable: AB and CD. I now heat the system until all bonds are broken. How do I achieve the following reaction: A+B+C+D -> AC + BD? What examples and methods can you think of?




Elementary type reactions will reach thermal equilibrium. The position of the equilibrium depends on the energetics and the temperature. The conditions are manipulated to give significant amounts of the material wanted and the reaction is kinetically stopped and the product isolated. There are many ways of doing this [most common is to simply remove a product]. A reaction can be quenched. The energy can be supplied in a specific manner such as photolytically, [photosynthesis], or by electrolysis, [batteries, plating]. There can be specific catalysis to separate competing reactions when the mechanisms differ enough. If a species is at a relative energy minimum there seems to be a method to characterize and possibly isolate it. I just looked up the half-life of Helium-5; it is 2x10^-21 sec. If that can be isolated anything can. When all else fails use a different method of synthesis! in your case A + C = AC and B + D = BD and be very careful how you mix them.


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