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Analysis has shown that the central Fe of heme is in the ferric state Fe+3.
If you ever burned Mg ribbon it is very hot and bright.
I was more concerned with questions like why is Chlorophyl, with its central Mg atom, photoactive, while heme with its central Fe atom is not, since both form using the same ring structures?
Like atoms within the resonance itself, these metal cations will cycle between reduced and oxidized states;
The central metal ions in Chlorophyl and Heme are forced to be electrophiles, that have to accept electrons that it would prefer give up. The metals are a captive audience.
The overall system wide stability comes at the expense of the central metal.
The central metal ions are placed in a state somewhere between metal and ion.
This also allows the resonance delocalization of the entire ring to expand further, even into the metal. The metal cannot leave because of this.
The selectivity for O2 is based on oxygen's high affinity for electrons
Quote from: puppypower on Yesterday at 13:21:13The central metal ions are placed in a state somewhere between metal and ion.No. They are charged ions.Quote from: puppypower on Yesterday at 13:21:13This also allows the resonance delocalization of the entire ring to expand further, even into the metal. The metal cannot leave because of this.If you remove the metal ions, the system is still delocalised.Quote from: puppypower on Yesterday at 13:21:13The selectivity for O2 is based on oxygen's high affinity for electronsThe selectivity for things like carbon monoxide is even higher, but it has little electron affinity.Why not study some science?That way you can avoid saying silly things.
If we are comparing metal-containing organic compounds, the blue blood of the horseshoe crab contains two copper ions in the hemocyanin molecule (when oxygenated). - It splits into two separate molecules (with 1 copper each) when no oxygen is present. Oxyhemocyanin_full.png (8.59 kB . 316x239 - viewed 4474 times)Image by Chemthulhu - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=39807956See: https://en.wikipedia.org/wiki/Horseshoe_crab#Harvest_for_blood
The mistake you are making is to assume ionic bonding and not covalent bonding with the central metal.
As I showed with benzene aldehyde
... resonance ring structures do no remain one way, as is often written.
The central metal of Chlorophyl and Heme does not see a uniform electron density, like an ion,
but it see electron density this is fluctuating with the resonance.
but covalent and based more on magnetism of electrons in larger scale motion.
I need to ponder why this is the case. What do these metals like about nitrogen
The central metal ions in Chlorophyl and Heme are forced to be electrophiles, that have to accept electrons that it would prefer give up.
Quote from: puppypower on 23/04/2021 13:52:22The mistake you are making is to assume ionic bonding and not covalent bonding with the central metal.The mistake you are making is not recognising that it is dative bonding.But that's probably because you refuse to learn science.Quote from: puppypower on 23/04/2021 13:52:22As I showed with benzene aldehydeThe stuff is called benzaldehyde.Making mistakes like that shows that you don't really know what you are talking about.Quote from: puppypower on 23/04/2021 13:52:22 ... resonance ring structures do no remain one way, as is often written. Actually, they do, but with (about) one and a half bonds each rather than alternating pairs of single and double bonds.You seem to have believed the "lies we tell to children" version.Quote from: puppypower on 23/04/2021 13:52:22The central metal of Chlorophyl and Heme does not see a uniform electron density, like an ion,Do you imagine that the sodium ion in salt sees a uniform electron density?Because, in reality, it doesn't.Quote from: puppypower on 23/04/2021 13:52:22 but it see electron density this is fluctuating with the resonance.NoAgain, you are looking at the nursery school version.The bonds don't "flip back and to".Quote from: puppypower on 23/04/2021 13:52:22but covalent and based more on magnetism of electrons in larger scale motion.No, chlorophyll and haem are not magnetic.Your determination to call everything "magnetic" just makes your viewpoint look silly.Quote from: puppypower on 23/04/2021 13:52:22 I need to ponder why this is the case. What do these metals like about nitrogenThey like the electrons.This is no shock. The metal ions are positively charged, the lone pair electrons are negative.It's simple electrostatics.It's also the reason why this is completely wrong.Quote from: puppypower on 22/04/2021 13:21:13The central metal ions in Chlorophyl and Heme are forced to be electrophiles, that have to accept electrons that it would prefer give up. Why not learn some science?The nitrogens don't need to be in a resonant system.You can tell that by thinking about the structures you have drawn in front of you, but you need to stop and think, rather than post tosh.If you think about it, you will realise that the other nitrogen- platinum bonds are stable. They stay in place while the cisplatin cross links the DNA. But in thus cases, the link is to ammonia which isn't a resonance structure.
The mistake that you are making is misunderstanding what oxidation states are.
Quote from: puppypower on 25/04/2021 13:01:16The mistake that you are making is misunderstanding what oxidation states are.I know that oxidation states are just an accounting tool.That's why the only time I used them was to point out where you were getting them wrong.You said this:Quote from: puppypower on 21/04/2021 12:09:17Analysis has shown that the central Fe of heme is in the ferric state Fe+3.And I cited the Wiki page which shows that, if the iron in your blood is ferric, you have a problem.You seem to forget that only one of us is actually a chemist, and you are the one making the mistakes you accuse me of.Why not learn some science?
. Not all theory can be scaled, since scaling involves other things such as the impact of mass and heat transfer, for example.
Statistics is not a statement of reality,
I could have used statistics
. It willingly shares a fraction of an electron density; probability function.
From the POV of scaling, a better water analysis is needed for life and metal coordination complexes are an expected part of life.
I aced all the chemistry final exams.
Once again there is nitrogen up close and personal with metals. I need to ponder why this is the case. What do these metals like about nitrogen and nitrogen within resonance structures?
This tool was too expansion when applied to all of chemistry including unique manufacturers molecules.
Photons can exceed the stability of the metal to deal with 4 times -3 electrons, in resonance, and allow a one election current.
This is not an ionic bond,
Quote from: puppypower on 25/04/2021 13:53:21This tool was too expansion when applied to all of chemistry including unique manufacturers molecules. Did you think that meant something, if so, what?Quote from: puppypower on 25/04/2021 13:53:21Photons can exceed the stability of the metal to deal with 4 times -3 electrons, in resonance, and allow a one election current. ditto.Quote from: puppypower on 25/04/2021 13:53:21This is not an ionic bond, Nobody said it was.On the other hand, I did point out that it''s a dative bond.
From years of observing your negativity and cynicism to everyone not mainstream, I have come to the conclusion that you memorize, but are not able to think on your own. You take the safe path, by attaching you wagon to consensus thinking and then become self righteous, criticizing anything not with the program. You are in the wrong section.
I will try to help you think,
outside the box might be scary for you.
What is the point of having the iron in the middle of the resonance ring, always confined to +2,
I am more interesting in developing new ideas
Sometimes a better mouse trap appears.