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dnt
Jan30-06, 01:10 PM
1. if you want to draw the electron dot structure for say carbon (4 valence electrons) would you draw it with one dot on each side or two on one side, and one on two other sides?

2. can someone give me a link that helps discuss hybridization - i dont really get it and i need help understanding it and trying to figure it out around central atoms. thanks.

AngelShare
Jan30-06, 01:38 PM
1. You would put one on each side. You have to add one to each side until you're out of valence electrons so everything is balanced. ^_^

2. I'm not really sure what that is...

dnt
Jan30-06, 02:32 PM
like sp2, sp3, etc...stuff like that.

GCT
Feb1-06, 05:19 PM
most of it is just standard rules. Try to pick up on the main concepts, such as the pauli exclusion principle and apply it. If you're working with VSEPER note that minimizing electron repulsion is one of the main themes.

dnt
Feb1-06, 05:37 PM
im pretty good at drawing lewis structures and naming the shapes but i dont quite get how to determine the hybridization around the central atom.

Valhalla
Feb1-06, 05:55 PM
It's been a while since I did this but this website gave a decent review on hybridization

http://chemistry.boisestate.edu/rbanks/inorganic/bonding%20and%20hybridization/bonding_hybridization.htm

aalmighty
Feb1-06, 10:54 PM
for determining hybridization, take into account the total electron pairs around the central atom, they maybe bond pairs, or lone pairs, the number of electron pairs is equal to the total number of hybridized orbitals (using pauli's exclusion principle, an orbital can't have more than 2 electrons with opposite spins)

confused? let's make it all clear with a couple examples

first we take up NH(3) (Ammonia)

Now, the central atom in ammonia is nitrogen, which has five valence electrons, three of them are shared by the hydrogens, and two are left unshared.

So the total number of Electron Pairs? There are 3 bond pairs and a lone pair, which makes the number 4, which means there are four hybridized orbitals.

Which Hybridization has 4 orbitals? sp3.

I hope this helps you, if there are any further questions, ask away.

benzun_1999
Feb3-06, 04:57 AM
i would like to add to aalmighty...............

this a small technique to calculate the hybridzation quickly.

for example take CH_4,
add Carbons' 4 valence electrons with the total number of valence electrons in all the hydrogen in the compound and divide by 2 ,

\frac{4+4}{2}=4

there four hybrid orbital hence it is sp3

similarly you can use this technique for other compounds also but when you have Oxygen or bivalent elements in the second place just ignore them and when you have ions take into consideration the no of electrons lost(cations) or gained(anions) by the chemical species.

here is some table that might help you

if there are 2 hybrid orbitals it is sp hybridized
if there are 3 hybrid orbitals it is sp2 hybridized
if there are 4 hybrid orbitals it is sp3 hybridized
if there are 5 hybrid orbitals it is sp3d hybridized
if there are 6 hybrid orbitals it is sp3d2 hybridized
if there are 7 hybrid orbitals it is sp3d3 hybridized