Is it true that the Second Law of Thermodynamics favours the spontaneous formation of complex molecules?

Is it true that really, really complex molecules can form spontaneously?

Is it true that the Second Law of Thermodynamics does not contradict the Theory of Evolution?

Science begins with, and is fundamentally based on, the observation of nature. Laws are derived based on what is seen always to happen in nature, and never to be violated. Since it is a fact that we never observe the spontaneous formation of really complex molecules, such as proteins and DNA, in nature, one should be suspicious of claims that such processes can happen. Processes that actually are spontaneous, such as combustion and rusting, are seen all the time.
Even the famous Urey-Miller experiment, in which H2, H2O, NH3, and CH4 were mixed in a chamber and sparked, yielded only a few simple amino acids (and these would have broken down immediately were they not removed from the system via a cold trap). No proteins or DNA were formed.
So, can really complex molecules form spontaneously? To answer this, we must consider the effects of entropy. What is entropy? According to McMurry & Fay’s Chemistry (Fifth Edition), “The amount of molecular randomness in a system is called the system’s entropy (S)…Molecular randomness is called entropy and is denoted by the symbol S.” (pp.298,650). Claims that entropy has nothing to do with disorder, then, are flawed. In fact, spontaneous natural processes tend towards increasing entropy, or disorder.
How, then, can really complex molecules, which are highly ordered, form spontaneously? You may have heard that simple H,N,O,C, and P, given an input of energy, become complex DNA as the energy drops, until at which point the final energy is lower than the energy at the beginning. You see that the DG is negative, and hear that the majority of biological molecules have DGf<0. There is a major problem here, however! We will illustrate this by considering glucose (C6H12O6), an organic molecule that is orders of magnitude simpler than DNA. Now, the DGf of glucose is -1250 kJ/mol. It is negative, yet glucose does not form spontaneously in nature, but only by the action of a chloroplast. Why is this? Because what matters is not the free energy of formation of the product but the free energy of the system (reaction mixture). It is this that determines whether the reaction is spontaneous or not (McMurry & Fay, p.662). And this is calculated from the heat of formation of the product minus the sums of the heats of formation of the reactants (McMurry & Fay, pp.668-669). In the case of glucose, the reaction is: 6CO2(g) + 6H2O(l) +2826 kJ ® C6H12O6(s) + 6O2(g) So the fact that DGf of glucose is negative is irrelevant; the reaction as a whole is endothermic and requires the input of 2826 kJ/mol. It does not occur spontaneously. By the same token, the formation of DNA or a protein, which would be far more endothermic, will certainly not proceed spontaneously. (It should be noted, in passing, that DNA would not be forming from elemental H, N, O, C, and P. These atoms would form simple compounds H2O, NH3, etc. in preference to forming highly complex DNA.) It is clear, therefore, that science agrees with observation that really complex molecules do not form spontaneously. The problem for the Theory of Evolution should now be obvious. It is absolutely essential to this “molecules-to-man” theory that at some point simple chemicals spontaneously formed vast amounts of really complex protein and DNA molecules. And that, folks, like it or not, is thermodynamically impossible. Therefore:

Is it true that the Second Law of Thermodynamics favours the spontaneous formation of complex molecules? NO!

Is it true that really, really complex molecules can form spontaneously?

NO! Is it true that the Second Law of Thermodynamics does not contradict the Theory of Evolution? NO!

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