Why is there no quadruple bond in carbon and carbon?
Like there is double and triple bond in O2 and N2, there can be even 4 bonds between carbon and carbon or silicon-silicon or any other element with valency 4. If this is not possible, then why cannot the carbon atom use the 4 resultant sp3 hybridized orbitals to form 4 bonds with another carbon? Also then why do describe about the C2 molecule in the Molecular Orbital theory?
Please try to explain me with the help of hybridization of orbitals.
September 30th, 2010 at 12:14 pm
It is one of those things you can talk about in theory but in nature it just won’t stretch and stay stable.
September 30th, 2010 at 12:21 pm
Ok, all atoms want to have 8 electrons in their valence shell. With that said, lets start. Carbon has 2 energy levels, so that means it has 1 s and 2 p orbitals. Now, a S orbital can carry 2 electrons, while P orbitals can carry 6. Carbon has its 1s orbital already filled with 2 electrons, but its 2p orbital only has 4,and its 2s orbital has none. REMEMBER THIS. PLS Bear with me, this isnt easy to explain online.
Carbon needs 4 electrons and how does it achieve it? Well, when it pairs up with another Carbon both Carbons contribute 2( due to their orbital properties) and so when both contribute 2, 2+2 equals 4. They share those 4 electrons and act as if they have 8 valence electrons.
If this doesnt make sense maybe this will:
Carbon has 4 valence electrons. It needs 4. If two Carbons were to be diatomically bonded with each other, each would give 2 because both “know” they are going to share the 4 electrons they need. That’s why there isnt a 4 pair bond, but a 2 pair bond. If two Carbons tried using the 4 pair bond, they would be sharing 12 electrons, something not possible.
I hope this helped, its been a very long time since I have taken Chemistry.