Chemical Forums
Chemistry Forums for Students => High School Chemistry Forum => Topic started by: princessyana on June 02, 2005, 06:32:30 PM
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I really need help to understand what hybrid orbitals are and how u can use them. I have a cumulative final coming up worth 20% and i'm borderline. *delete me* :' ???
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Blimey, I'd reccomend you look up hybridization in your set organic chemistry text.
Its most obvious in carbon, where one s and 3 p orbitals mix to form 4 'sp3' orbitals which are degenerate.
Rules to remember:
1) Always conserve number of orbitals when hybridizing.
2) When finding hybridisation state, start with sp3 and take away one p for each double bond to that carbon.
3) sp and sp2 stabilise negative charge better than sp3, and so are more acidic.
4) sp is linear, sp2 is triagonal planar, sp3 is tetrahedral.
Need more depth?
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VSEPR is a good heuristic rule for deciding the hybridised state of the central atom.
the hybridised state depends on the number of electron group (in the valence shell) surrounding the central atom. a double bond is considered as an electron group. a lone pair is considered as an electron group. a single bond is a considered as an electron group. a triple bond is considered as an electron group. an unpaired electron is considered as an electron group.
if there are 6 electron groups, the hybridised state is sp3d2
if there are 5 electron groups, the hybridised state is sp3d
if there are 4 electron groups, the hybridised state is sp3
if there are 3 electron groups, the hybridised state is sp2
if there are 2 electron groups, the hybridised state is sp
There are exceptions to this rule, but this should be sufficient to suffice for use.
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Allow me to ask a dumb question if you will..
How is possible that Carbon has 3p orbitals? Arent the shells filled like this:
1s(2)2s(2)2px(1)2py(1). Would appreciate a quick clarification! ???
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Just because an electron doesn't occupy an orbital doesn't mean the orbital doesn't exist. ;)