Summary of session 8

1. The equilibrium constant of a reaction is fixed at any particular temperature. It depends only on the natures of the initial reactants and the final products; what happens as reactants change into products has no effect on the equilibrium constant or position of equilibrium.
2. The rate of a chemical reaction is affected both by the temperature and by the pathway (reaction mechanism) through which reactants change into products. This pathway can sometimes be altered, for example by the introduction of a catalyst.
3. The catalyst causes a change in the reaction mechanism which leads to a lowering of the energy barrier and to a greater rate of reaction.