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Question by Gary Novak
Is it not true that kinetic energy cannot be transformed into chemical energy?
I'm a biologist. The so-called biophysicists who study ATP (adenosine triphosphate, the universal energy carrier in biology) derived a theory which contradicts principles of physics. Tell me what you think about it.
I have a web page on this; and I'll describe it here. (You can skip lightly through the preliminary context and focus on the physics below it.)
Energy is restored to ADP (adenosine diphosphate) by connecting a third phosphate in a chain. Respiration does this. The energy originates with a hydrogen atom which has a high energy electron associated with it. The electron spins through a series of cytochromes and mysteriously kicks up the energy level of a phosphate bond allowing it to be attached to the ADP.
Biophysicists detected an osmotic gradient across a membrane and a spinning wheel which picks up the phosphate and attaches it. So they theorize that the chemical energy is enhanced by the force of the spinning wheel, which is set in motion by the hydrogen moving across the osmotic gradient.
The reaction site is made up of proteins which are called a binding site. Supposedly, the binding site first picks up kinetic energy from the rotating wheel. It then supposedly creates a force which increases the energy of the electrons which bind phosphate to ADP.

The contradictions to physics principles are these:
First some truisms: chemical energy is in the orbit of electrons which bind organic molecules together by orbiting more than one nucleus; kinetic energy is in the motion of mass, which means nucleus; force is either converted to kinetic energy or potential kinetic energy, if it's an elastic force.
It is totally impossible for kinetic energy to be directly converted into chemical energy. The reason why is because the motion of nuclei cannot influence the motion of electrons.
Only radiant energy can increase the net energy of electrons. It does so by synchronously enhancing the orbital energy of electrons numerous times over several orbits. This is why wavelengths are important in absorption and emission of radiant energy by matter. The wavelength determines whether the radiation waves synchronize with the electron orbits.

So binding force cannot be converted to chemical energy in attaching phosphate to ADP to create ATP. Biophysicists are wrong in claiming binding force is transformed into chemical energy in attaching phosphate to ATP.
Do you agree?
Here is a link to a web site on ATP Synthase and here is a link to my web page criticizing the subject.

Reply
From a viewpoint of classical mechanics it is certainly true that a nucleus can not transfer its kinetic energy to an electron or vice versa, because the energy transferred is only a fraction of the kinetic energy (as given by the ratio of the smaller to the greater mass). Regards the difference of velocities addressed on your webpage: although electrons in atomic orbits do not move with the speed of light (as you state on your webpage) but only with about 108 cm/sec, this is still several orders of magnitude faster than thermal nuclei, and an approaching proton would therefore 'see' the electron as a quasi- stationary charge distribution (as you correctly pointed out). However, for nuclei orbited by electrons themselves, there would be the possibility of electron-electron collisions which would enable the electrons to rearrange their energies (on the basis of this (purely classical) mechanism, I have for instance proposed an autoionization process which could explain the high electron density in the ionosphere of the earth at night; from the night-time electron density one can estimate that this ionization occurs with an effective cross section of about 10-20 cm2, although this can be expected to be strongly temperature dependent).

However, I would expect that in biological systems, the reactions involve energies corresponding to the thermal velocities of nuclei, i.e.quantum mechanical vibrations and rotations of the molecular nuclei are being excited. These in turn could either radiate this energy away or transfer it again to other nuclei as kinetic energy (this is how energy equilibrium is established in the lower regions of the earths atmosphere; in the highest regions there are mainly atomic constituents which can only be excited by electrons because their energy is high enough). Electronic states could only be excited by nuclei if one has a sufficient energy to compensate for the small electron/nucleus mass ratio, i.e. an energy of several keV, which I think is highly unlikely in biological systems).

A further point is that energy conservation (in fact the notion of energy) can only strictly be applied in classical physics (more) but not in connection with atomic radiative processes. I have suggested that this circumstance could actually explain the excess energy observed in electrolysis experiments ('Cold Fusion').

As mentioned, I think your arguments are correct in the context of classical physics, but I am sure the problem has to be treated as a quantum mechanical process, i.e. as an inelastic collision between the protons and molecules.

Gary Novak(2)
Thanks for the analysis.
There doesn't appear to be anything in your description indicating that kinetic energy can be directly converted into chemical energy.
If close proximity of nuclei result in electrons exchanging energy, that is purely a chemical reaction.
So there doesn't appear to be any reason to modify my ATP paper stating that binding force cannot restore the chemical energy of ATP.

Reply(2)
It all depends on what you mean by 'chemical energy'. As already indicated in my last email, classically there is only kinetic and potential energy. Both can momentarily be converted into each other, but on the average they are constant in a closed system (the virial theorem shows that for a system of particles bound by the inverse square law force, the kinetic energy is (minus) half the potential energy). In order to change the energy of the system you have to either remove or add a further particle. If you do the latter, you can not create a new stable system if the energy of the new particle is very high, because if the total energy becomes greater than zero, you don't have a bound system anymore. You can therefore for instance only create negative ions, if you attach very low energy electrons to an atom. The same should hold for reactions of molecules, i.e. you can add two molecules with a low kinetic energy together to form a new molecule, but not molecules with a high kinetic energy.
Classically the problem is therefore completely determined by mechanical energy conservation.
As indicated by me earlier however, most chemical reactions are of a quantum mechanical nature, i.e. they do not necessarily conserve mechanical energy, because part of it is turned into radiation. The latter may again be absorbed by molecules and turned into kinetic energy again, but in general energy will not be exactly conserved here because there is no energy conservation law for the intermediate state involving the radiation.

Anway, I have found some information on the internet which states that the electric potential involved in the ADP to ATP conversion is about 300mV (=0.3 V). Now, even if electrons (let alone protons) are accelerated in this field, their energy would in general not be enough to excite electronic transitions of the molecules, whereas it would be suitable (for the protons) to excite vibrations and rotations of the molecular nuclei or alternatively to form new molecules.

Gary Novak(3)
Chemical energy is entirely in electrons. There must be a shift in electron orbits to yield chemical energy or transfer it to other molecules.

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