Why can't carbon form bond of 4 electrons with another carbon ?
Why can't carbon form bond of 4 electrons with another carbon ?
The reason is to have those bonds all four pairs of electrons must be present between two carbon atoms and only on 'one' side of each carbon atom which is geometrically impossible for all kinds of hybrid orbitals. No! Carbon-Carbon quadra bond is invalid. ... It is bonded covalently with 4 other Carbon atom. From a Lewis point of view, there is no reason why carbon can't form a quadruple bondsatisfying the Octet Rule and leaving no electrons for further bonding. But it implies that C2 is a perfectly stable molecule, like N2, and that just isn't the case.
If we go on to the valence-bond model, in which bonds result from the overlap of atomic orbitals, we see a better explanation: carbon cannot form a quadruple bond because it doesn't have enough atomic orbitals pointing in the right directions. sp hybridization leaves two p orbitals over, while sp2 hybridization leaves one p orbital.
Valence-bond theory predicts two possible bonding states for C2:
1. double bond with all electrons paired, :C=C: (as seen in Alkene)
2. a triple bond with two unpaired electrons, .C(Triple)C. (As seen in Alkyne)
These are called resonance structures, and both must be considered as partial representations of the real situation.
From a Lewis point of view, there is no reason why carbon can't form a quadruple bondsatisfying the Octet Rule and leaving no electrons for further bonding. But it implies that C2 is a perfectly stable molecule, like N2, and that just isn't the case.
If we go on to the valence-bond model, in which bonds result from the overlap of atomic orbitals, we see a better explanation: carbon cannot form a quadruple bond because it doesn't have enough atomic orbitals pointing in the right directions. sp hybridization leaves two p orbitals over, while sp2 hybridization leaves one p orbital.
Valence-bond theory predicts two possible bonding states for C2:
1. double bond with all electrons paired, :C=C: (as seen in Alkene)
2. a triple bond with two unpaired electrons, .C(Triple)C. (As seen in Alkyne)
These are called resonance structures, and both must be considered as partial representations of the real situation.
