Free Energy is the energy available to do work 5. Exothermic processes with decreasing entropy will be spontaneous at low temperatures, non-spontaneous at higher temperatures 6. Endothermic processes with increasing entropy will be non spontaneous at low temperature and spontaneous at high temperatures 8. At equilibrium , rates of forward and reverse reactions are equal 9. Free energy of an actual process is determined by relationship between the standard free energy and the equilibrium constant.
Catalysts reduce the activation energy necesary for a process to occur.
In chemistry we relate macroscopic, observable change to transformations at the molecular level that go unseen through the shorthand of symbolic representation. For the most part, we are comforted by the fact that we can at least observe the macroscopic. Here is a wonderful representation of the way chemical reactions take place that may help you understand chemical kinetics and thermodynamics. Although tetraethyllead left its own toxic trail, the human toxicity of lead compounds was not the driving force for the removal of TEL from fuels. Eventually TEL was removed to make way for the catalytic converter in an effort to reduce the damage from nitrogen oxides and ozone.