The primary force that binds hydrogen atoms to form H2 is the electromagnetic force, specifically the electrostatic interaction between protons and electrons. As two hydrogen atoms approach each other, their electrons occupy a lower energy bonding orbital, resulting in a double covalent bond. This interaction is characterized by a symmetric wave function energy level, which is more stable than the antisymmetric one. The discussion also touches on the nature of intramolecular forces, including metallic, ionic, polar covalent, and non-polar covalent bonds.
PREREQUISITESThis discussion is beneficial for chemistry students, educators, and anyone interested in understanding atomic interactions and chemical bonding, particularly in the context of hydrogen and molecular formation.
A more 'noddy' description (a description without QM that would have satisfied a Victorian, perhaps) could be that each atom shares each electron. The attraction between each proton and each electron pulls the two protons together until their mutual repulsion balances out the attraction. This covalent bonding happens in many other molecules and describes how large molecules with chains of Carbon atoms (in particular) can exist. School Chemistry describes the bonding between some atoms of different elements as 'ionic bonding'. In that case the model is that one electron moves from one atom to the other and actually forms two ions. (Google it).Orodruin said:You are correct that the interaction is electromagnetic. It is a matter of how the electrons and the nuclei interact and those are charged.
Very simplified: If you have two hydrogen atoms infinitely far away from each other all energy levels of the electrons will be degenerate. As the protons come closer together, this degeneracy is broken and there will be one symmetric wave function energy level where the electrons on average will be likelier to stay between the protons that has a lower energy than the antisymmetric one. Placing both electrons in this energy level (possible due to spin) is a double covalent bond.
A similar question would be why negatively charged ions can exist.
Two electrons in a bonding orbital constitute a single covalent bond. Just one electron (as in H2+) would give a bond of order 1/2.Orodruin said:Placing both electrons in this energy level (possible due to spin) is a double covalent bond.
sophiecentaur said:A more 'noddy' description (a description without QM that would have satisfied a Victorian, perhaps) could be that each atom shares each electron. The attraction between each proton and each electron pulls the two protons together until their mutual repulsion balances out the attraction. This covalent bonding happens in many other molecules and describes how large molecules with chains of Carbon atoms (in particular) can exist. School Chemistry describes the bonding between some atoms of different elements as 'ionic bonding'. In that case the model is that one electron moves from one atom to the other and actually forms two ions. (Google it).
Also, Metals are held together very strongly because the outer electrons are shared by many adjacent atoms, (a form of covalent bonding, if you like). As the metal is stretched, the electrons keep pulling and they latch onto different atoms. So the metal doesn't break because other bonds are formed.
Orodruin said:there will be one symmetric wave function energy level where the electrons on average will be likelier to stay between the protons that has a lower energy than the antisymmetric one.
No. The symmetric/antisymmetric here refers to a parity transformation of the spatial wavefunction. In general, if you have a symmetric potential as in the case of the two protons, the wave function of the energy eigenstates will be either symmetric or anti-symmetric.heavybuilder said:I think I found an answer: but i still don't get what Orodruin was saying
symmetric waves: particle interchange with bosons
antisymmetric waves: particle interchange with ferminons
heavybuilder said:Can somebody explain this? ^
Where did you get that idea? I was talking about electrons and protons. That's electrostatic (Coulomb) Force.heavybuilder said:So no electromagnetic force but intramoleculair forces?