Bond Example
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Bond Example
I know we went over why carbon can form 4 bonds when it only has 2 lone pairs, but I do not understand it thoroughly. Can someone explain why this is in simpler terms?
Re: Bond Example
A normal carbon atom has 2 unpaired valence electrons and 2 electrons that are paired to one another with normal orbitals.
A covalent bond is given by a sharing of one unpaired valence electron from one atom with the same of another.
Under this understanding carbon would only be able to make 2 bonds with the orbital model but somehow it makes 4.
If we were to model a covalent bond under the model of atomic orbitals it wouldn't make sense that carbon can make 4 bonds.
This can be explained using hybridization because in a covalent bond the orbitals are not the same as the atomic orbitals.
The orbitals are changed in carbon depending on the amount of bonds it forms. In this case, carbon would make 4 bonds so we would want the carbon to have 4 unpaired electrons.
In say methane(CH4), the orbitals are no longer [He ]2s^2 2Px^1 2Pz^1 but [He] 2sp3^4 meaning that they are no longer shaped as they normally would. All the electrons are now unpaired and can be used for bonding. This can be explained by Hund's rule.
In atomic carbon there is one 2 s orbital of lower energy then the three 2 p orbitals of higher energy. Because the s is of lower energy it is more energetically favorable for it to fill completely then start filling the p orbitals.
In molecular carbon where there is 4 bonds, there is instead 4 sp3 orbitals which since they are of equal energy to one another fill one electron in each orbital first. 4 valence e in carbon with 4 shells means one electron per shell which means they are all unpaired.
A covalent bond is given by a sharing of one unpaired valence electron from one atom with the same of another.
Under this understanding carbon would only be able to make 2 bonds with the orbital model but somehow it makes 4.
If we were to model a covalent bond under the model of atomic orbitals it wouldn't make sense that carbon can make 4 bonds.
This can be explained using hybridization because in a covalent bond the orbitals are not the same as the atomic orbitals.
The orbitals are changed in carbon depending on the amount of bonds it forms. In this case, carbon would make 4 bonds so we would want the carbon to have 4 unpaired electrons.
In say methane(CH4), the orbitals are no longer [He ]2s^2 2Px^1 2Pz^1 but [He] 2sp3^4 meaning that they are no longer shaped as they normally would. All the electrons are now unpaired and can be used for bonding. This can be explained by Hund's rule.
In atomic carbon there is one 2 s orbital of lower energy then the three 2 p orbitals of higher energy. Because the s is of lower energy it is more energetically favorable for it to fill completely then start filling the p orbitals.
In molecular carbon where there is 4 bonds, there is instead 4 sp3 orbitals which since they are of equal energy to one another fill one electron in each orbital first. 4 valence e in carbon with 4 shells means one electron per shell which means they are all unpaired.
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