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Hydrogen bonding in water


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Is hydrogen bonding in water the result of the hydrogen bonding to the bonded electrons of oxygen or is it a mutual things due to electrostatic attraction between oxygen and hydrogen. In other words, a one-way potential or a two-way potential.

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Is hydrogen bonding in water the result of the hydrogen bonding to the bonded electrons of oxygen or is it a mutual things due to electrostatic attraction between oxygen and hydrogen. In other words, a one-way potential or a two-way potential.

 

Hydrogen bonding, without it it life cold not exist. Itf formed by the higher electronegativity of the Oxygen trying to pull the electrons closer to its self and in doing so gives the Oxygen atom a slight negative chanrge and the Hydrogen atoms a slight positive charge. This is known as a polar molecule.

 

In water, as per two magnets attracting one and other, the slight positivley charged Hydrogens are drawn to the slightly negative Oxygen atoms and vice versa creating a large set of electrostatic bonds, these give water its cohesive properties and ais also why ice is less dense than water and why water is such a good solvant :) So, I'd say it is a two-way potential.

 

Did that help at all?

 

Cheers,

 

Ryan Jones

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Thanks RyanJ. I am still a little confused. When a water molecule forms, the higher electronegativity of oxygen allows oxygen to hold extra electron density to form an anion. This anion is stable due to magnetic addition of the electrons within the oxygen orbitals. The hydrogen, on the other hand, is induced to have a potential. This should cause the water molecule to have its overall potential localized on the hydrogen side. The charge dipole adds to zero but the EM force is both electro-static and magnetic.

 

In a physics forum I posted a topic called exothermic dipoles. I used the example of metallic iron and oxygen gas reacting to form iron oxide. What we begin with are two charge neutral materials becoming three dipoles while giving off energy. The iron cation will now have more protons than electrons, the oxygen anion will now has more electrons than protons and two neutral materials will now become an ionic dipole. Using electrostatic alone would appear to violate the laws of physics, but if one takes into consideration the EM force being both electrostatic and magnetic the math adds up.

 

In the case of water the exothermic magnetic addition within oxygen allows it to become an anion (atomic dipole). The hydrogen will lose magnetic addition (magnetic subtraction) to also become an atomic dipole. The dipoles within water may balance but the induced magnetic subtraction within the hydrogen should define a slight potential compared to the stable magnetic addition of the oxygen. Within liquid water the hydrogen should be on the hunt. It just so happens that only oxygen is available to share electron density.

 

Although the charges may cancel, the magnetic gain of the hydrogen will cause the oxygen of water to lose magnetic addition. The oxygen will attempt to reform magnetic stability and pass the burden of potential back to its own hydrogen, etc. The pH in water at neutral conditions implies a covalent bond becoming an ionic bond. This change of bonding state should be endothermic. If one constantly extracted the pH dipole water out of the water, the pH effect would continue to reform. This self perpetuating endothermic change of bonding state needs to be pushed forward from zero by a self perpetuating exothermic potential. The potential comes from the orbital magnetic stability of the oxygen passing the potential off to its hydrogen (hydrated -OH and hydrated H+).

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Remember that electrons are not static beings. They are constantly moving all over the atom(s) and are not localized. While the oxygen may have the negative charge for a breif moment, just as suddenly it can lose that charge and become more positive. It's just that on a long term basis, the electrons tend to spend more time around oxygen than they do hydrogen.

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its because Oxygen has 2 unpaired electrons. These therefore mean that oxygen becomes slightly negatively charged (aswell as the fact that the probability of finding electrons closer to the oxygen is greater than the other way round). This gives oxygen a slightly negative charge (or delta negative) and hydrogen a slightly positive charge (delta positive). because of this each hydrogen atom is attracted to an oxygen atom of another molecule. This explains cohesion between the molecules and also the abnormaly high boiling point of water. it easily dissolves ionic compounds as these can also form temporary bonds between the water molecules. This also explains why the latent heat of water is huge 4.2kjkg-1k-1 (this is the amount of heat energy ,in kelvin, 1kg of water can absorb) this explains why burns from boiling water are very painful

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I agree with that. The goal I am looking to achieve is connected to seeing if the hydrogen bonding hydrogen are the business end of water molecules. The charge dipole says no, but the higher electronegativity of oxygen says yes. The oxygen is stabilized being an anion or it would not have taken electron density from hydrogen in the first place. The hydrogen should bare a potential stemming from oxygen's stability. If the dipole cancels, then it needs to be magnetic or something.

 

My longer term project is connected to cellular modeling using hydrogen bonding. Everything in the model appears consistent but nobody seems to be able to get past the hydrogen bonding dipole. If hydrogen bonding hydrogen is the holder of a potential that means that a hydrogen bond that is not optimally formed retains a slight electrophilic potential that was originally created by O or N. The oxygen and nitrogen don't need the positive charge but are already stable with the added electron density or else they would not have taken it from hydrogen in the first place. If we add this slight electrophilic potential up within highly hydrogen bonded materials like biomaterials, these will define an accumulative electrophiic potential. This allows me to position materials in an electrophilic gradient between the cell membrane and the DNA.

 

If the H-bond is only a dipole this analysis is an illusion. Biologist and biochemists can only see a dipole. I'm I missing something with my logic?

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I agree with that. The goal I am looking to achieve is connected to seeing if the hydrogen bonding hydrogen are the business end of water molecules.

 

It depends on how you look at it - these bonds give it its cohesive and solant properties.

 

At what level are you stddying? Have a look at this and also this - its the first place I look for chemistry type answers like these :D

 

Cheers,

 

Ryan Jones

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If we look at hydrogen gas reacting with oxygen gas to form water, this highly exothermic reaction begins with two hydrogen atoms and two oxygen atoms. Both are neutral with respect to their nuclear proton and electrons.

 

This highly exothermic reaction results in the hydrogen ending up with less than a full equivilent of one electron to make it charge neutral. The oxygen atom ends up with too many electrons to make it charge neutral, i.e., anion. This is benificial to the oxygen because it completes an octet of electrons within its 2S, 2P orbitals.

 

If we start with a hot gas of ionized hydrogen atoms, these hydrogen atoms will retain one electron within higher orbitals even at these high temperature. In water at room temperature, the hydrogen is induced in a state of having less than one full electron to share or within a state where the electrons are pseudo-ionized in orbitals higher than 1S, i.e, covalent bond. This is very loosely analogous to the hot ionized hydrogen with a potential in the order of 10kcal/mole.

 

Hot ionized hydrogen could release potential at room temperature. But the hydrogen of water is already at room temperature and needs to share electron density to lower its potential. The oxygen of water, which released energy to get to its stable octet will now need to gain energy or enter an excited state before it can share electron density with hydrogen. This endothermic reaction is supplied energy by the hydrogen lowering potential to form a hydrogen bond.

 

If a stable hydrogen bond is not optimized, the hydrogen can not release enough energy to fully endothermic ionize the stable octet electrons of oxygen. This results in residual potential existing in the hydrogen and less potential being endothermic induced in the oxygen. The electrons of hydrogen are still partially in the 2S orbital and would like to drop even further.

 

Within large biomaterials hydrogen bonds are not always optimized. This positions residual hydrogen boniding potential throughout the biomaterial. Being one covalent molecule, the biomolecule will try to move some of its electron density around to help minimize this potential. If this does not completely work, then the biomaterial will define electrophilic potential. Biomaterials, such as enzymes, which all have a surface active site, will all create excited states of reactants. These exicited states allow enzymes to temporarily share electron density.

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