MisterDax Chemistry Tutorial

phooney
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MisterDax Chemistry Tutorial

This is a post aimed at MisterDax, who posted in another one of my threads, helping out with some chemistry.  However, anybody who is also well versed in the field, I would certainly appreciate the help/opinions.

In my other thread "intelligent design debate I'm having at the moment", I said I was presented with an argument based on a chemical equation of G=H-TS, saying that for the reaction of life to occur, certain values that supposedly can't logically happen must happen.

MisterDax explained that this equation describes an equilibrium and for all values of G, it doesn't mean that reactions aren't occurring in both directions.

However, you might be forgiven for thinking that some theists don't give up easily, so I would like to draw on the knowledge of this forum to help me understand exactly what is being argued against me.

So without further ado, the relevant pieces of the conversation at the moment:

His original statement:


"G is free energy. Its a term used to describe whether a reaction will be spontaneous (here spontaneous means the reaction can occur). H is enthalpy, the amount of heat absorbed or given off by the system during the reaction. T is temperature. S is entropy, the randomness of a system. S is positive if the system becomes for random. In order to create life, energy must be absorbed, which makes H positive. Life is less random than no life, so S is negative. T is always positive cuz we use Kelvin scale. G=H-TS. With the variables as they are, G must be postive. As already stated, if G is positive the reaction will not occur. That is evidence for ID. The reaction, based on our understanding of Thermodynamics, should not be able to occur. But obviously it did."


Followed by what myself and another posted regarding what MisterDax explained.

Then:

"“Of course I haven't disproven anything, because there's been no evidence provided. The closest thing I've seen the ID crew come to evidence is Jimmy/The Cringe's formula about the change in G. Unfortunately upon further research it came to light that his equation did not mean quite what he thought it did.” – Phooney

Please enlighten me. Because I’m a Chemistry major. I’ve done my thermodynamics studies and this is an equation I have looked deeply into because of its contradiction with evolution. I have had long discussions with several PhD Chemistry Professors, one of which is so renowned that he has been the first citation in over a dozen Nobel Prize winning speeches. (He invented mass spectroscopy. Most people can’t believe he himself doesn’t have a Nobel Prize.) Each of these people has told me that my logic and reasoning is correct; that this equation does contradict evolution in many ways. If all of these very intelligent people and I are wrong, then please, enlighten me as to how. "


This is somebody that describes themselves as agnostic:

"I posted somewhere up there about the delta-G thing. delta-G values are calculated at standard concentrations (1 M in most cases), but get infinitely large as you move towards 0 concentration of the products of a reaction. No matter what value a delta-G is, it doesn't say the reaction doesn't happen, it is used to calculate the equilibrium level as the reaction goes back and forth. When the delta-G is so negative that the equilibrium level is less than 1 product (molecule or in this case perhaps cell), it indicates how often over time that product is expected to present as it appears and disappears. In the case of life, thermodynamics doesn't disprove its origin from chemicals or whatever we are debating here."

The theist's response:


"Wrong, delta-G (subscript 0) is at STP. That means 1 atmosphere pressure and 25 degrees Celsius, not standard concentration. The equation has nothing to do with concentrations. delta-G (without a subscript) is for whatever pressure and temperature you are addressing. As I already stated, delta-G tells us if a reaction will occur. It must be negative for a reaction to occur. Based on the entropy and enthalpy required in the creation of life, an educated chemist will tell you that the pressure and temperature required for the creation of life is extremely large. So large that most scientists belive these states were never present on the Earth."

Agnostic:


"Okay, the delta-Gs that are massively positive are the ones at standard concentrations. That inhibits forward reactions of the system, but reactants and products still goes back and forth. As concentrations get lower, the delta-G of the reaction gets more negative. When it is at equilibrium, delta-G is 0. When products are 0, delta-G is technically infinitely positive. No matter what the delta-G at any concentration, it doesn't mean it won't ever go forward; molecules and systems move rapidly around their equilibrium and tend back towards it when they are away from it.

PS I had my signs wrong in the last post."

Agnostic quickly posting a correction:

"Dammit, I meant when products are 0 then delta-G is infinitely negative. That's what I get for trying to do too many things at once."

Theist:


"Correction to my previous statement. I belive you may be referring to the equation (I'm gonna ignore writing deltas):

G= G(sub0)-RT/nF*ln(([A]^a*[B]^b)/([C]^c*[D]^d))

In this case, concentrations of products and reactants do matter. however, G(sub0) is a constant, it doesn not depend on temp. pressure, concentration, ect. For the reactions involved in the creation of life(and I mean the very small, extremely earlier substeps leading towards actually life) G(sub0) is extremly large. The concentrations of the reactants A and B would have to be incredibly large and the concentrations of the productsC and D would have to be incredibly low. Yet in the next reaction, C and D are the reactants, E and F are the products. C and D concentrations have to be incredible large for this next reaction but they have to be incredibly small for the first reaction. Does anyone else see a problem?"


Agnostic:

"Well that depends on what you consider the product with the infinitely large delta-G. If you say that the equilibrium concentration of the reaction with a single cell as the product and all its components as reactants, in all the universe, is such that 1 will exist for 1 day out of a billion years, then once that cell exists it starts making more of itself. All the world is away from equilibrium, and not just in regards to life. All it takes is for one cell to exist long enough to start reproducing before it dies.

And yeah, that equation is infinitely negative when the products are 0."

Theist:

"Lol. you had your signs right the first time. delta-G becomes more negative as concentration of reactants increase and concentration of products decrease. My bad for confusing you the first time. But as I said. If the first reactions prodeucts become the second reactions reactants, how can they be low concentration for the first and high concentration for the second. The first reaction won't allow them to reach the concentration needed for the second reaction.

Obviuosly there could be some order of reactions that allow the creation of life to be compatible with this equation. But based on all steps we have currently thought of, creation contradicts thermodynamics. So right now, based on science, thermo supports points towards the laws of physics being broken. To me, the breaking of a law of nature is a divine act. Guess it just depends on what you consider divine."

Agnostic:

"I think we are coming closer to agreement. Last I read about it they still had to figure the most likely stepwise creation of life that would have occurred for it to have been likely. But that doesn't really rule it out in my mind. Obviously some self-replicating unit had to have formed at some point, and then it was able to reproduce itself away from equilibrium."

Theist:


"Actually, from what I have read, they have been able to get the steps correct. they can get a biological organism t be produced, but they cannot get it to replicate. It is the steps involved in replication that are where the improbablity arrises."


 


Cpt_pineapple
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Wouldn't the system have to

Wouldn't the system have to be adiabatically isolated?


phooney
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Don't let me down, chemists!

Don't let me down, chemists!


monkeyfishfrog
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First off, the fact that he

First off, the fact that he does not understand this simple concept is yet another condemnation of the state of undergraduate physical chemistry educatoin in this country. Now to the question. In the course of a sponaneous reaction, the change in Gibbs energy must be negative. In the instance in question, the change in enthaply is postive and the change in entropy is negative. This makes the first term positive and the second term negative. The MAGNITUDES of the terms as well as the signs determine whether the process is spontanteous. Also, do not forget that temperature also plays a role. These numbers are completely impossible to quantify, because we do not have a complete theory for abiogenesis.

The tangential conversation about concentrations is irrelevant. Yes, you can force the creation of any product given high enough concentrations, but that is not a route that I have ever seen used in theorized prebiotic pathways.


Susan
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monkeyfishfrog

monkeyfishfrog wrote:

First off, the fact that he does not understand this simple concept is yet another condemnation of the state of undergraduate physical chemistry educatoin in this country. Now to the question. In the course of a sponaneous reaction, the change in Gibbs energy must be negative. In the instance in question, the change in enthaply is postive and the change in entropy is negative. This makes the first term positive and the second term negative. The MAGNITUDES of the terms as well as the signs determine whether the process is spontanteous. Also, do not forget that temperature also plays a role. These numbers are completely impossible to quantify, because we do not have a complete theory for abiogenesis.

The tangential conversation about concentrations is irrelevant. Yes, you can force the creation of any product given high enough concentrations, but that is not a route that I have ever seen used in theorized prebiotic pathways.

I admit that went completely over my head!

However, welcome monkeyfishfrog.  Smile

When you get a chance, hop on over to General Conversation, Introductions, and Humor and introduce yourself! 

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