Bonding of Carbon

[SarCaustic]

Can anyone explain the bonding and structure of carbon in benzene to me with reference to the electron orbitals and hybridisation?
Here's what I already know:
C<sup>12 electron configuration: 1s2, 2s2, 2p2
Excitation causes one of the 2s electrons to become a 2p electron.
Then 2 of the 2p electrons and one of the 2s electrons hybridise formind a 2 sp2 hybrid orbital. The C-C bonding in benzene in formed by the single overlap of the 2 sp2 orbitals on adjacent C atoms. The bond formed is 0.139nm long - in between the length of a single bond and a double bond. Is the C-H bond the same?
Each carbon has 1 valence electron (which occupies a P orbital) remaining. The Pi bond is formed by the double overlap of the P orbitals.
Have I got anything wrong or missed anything?
I'm an A Level student and I inquired about this - my teacher briefly explained and I wanted to see how much I remember and how much of it is right. I have an interview at Newcastle University for Medicine on Monday and I think I'll mention this if they ask whether I've encountered anything interesting in the subjects I'm studying.
Incidentally, how does the bonding in a saturated carbon compound differ?
Thanks in advance,
SarCaustic

[Law Student]

There must be some good sources of information on the internet, but basically you're correct. You should note that the C-H bond is a different length to the C-C (should be longer, but you can look it up).

In a saturated organic molecule you're only dealing with 2sp3 orbitals, arranged roughly tetrahedrally (depending on the other atoms involved.

[knobbynonuts]

try wikapeada the best website for stuff like that

[Gef]

It is not the electrons which hybridise but the atomic orbitals.

In benzene, sp2 hybridisation takes place producing 3 hybrid orbitals at 120 degrees to each other. These hybrid orbitals each containing one electron form 3 sigma bonds with two carbon atoms and one hydrogen atom.

That leaves one unhybridised p orbital, containing one electron, on each carbon atom. These overlap around the ring to form pi bonds.

In benzene the bond lengths are: C-C 140 pm and C-H 109 pm. (Values vary slighly depending on where you look them up).

In saturated compounds sp3 hybridisation takes place producing 4 identical orbitals in a tetrahedral arrangement. These form sigma bonds with other carbon atoms and hydrogen atoms. The bond length is 154 pm.

[Gef]

PS Good luck with the interview.

[SarCaustic]

Thanks for the help. The interview's tomorrow!