Chemistry ( Butadiene Question )

[virtueixi]

Please do not flame this thread. I have been trying to get the answer to this problem since this morning. I am soaking wet as I tried to get a TA to help me, but as it turned I knew more than her, so as I was leaving it started to pour. This is my last question on the set and it is due tonight. ANY help would be appreciated:

Pic from http://capa.chem.sunysb.edu/nan/butadiene.gif (of Butadiene )

Consider the delocalized pi orbitals of butadiene (above). Which of the following statements are true ?



a) Butadiene has 2 pi orbitals

b) Butadiene has 8 pi electrons

c) The highest energy pi orbital in butadiene has no nodes besides the plane of the molecule

d) Butadiene has two filled pi orbitals

e) The highest energy filled pi orbital in butadiene has one node, besides the plane of the molecule

f) The highest energy filled pi orbital in butadiene is antibonding between carbons 2 and 3


Could be several answers. Thank You

 

[virtueixi]

thx anyway

 

[Apathetic]

You may have better luck with this in the "Highly Technical" forum.

Dave

 

[bastula]

I think A is true, since C1 and C2 share one pi bond, and C3 and C4 share another pi bond.

I know at least answer B is true, since each pi bond will have 4 electrons.

I am not sure about C, since I don't really remember nodes.

D is true since A is true - makes sense to me...

Not sure about E.

I think F is true - take a look at this link at figure 7.9: http://wps.prenhall.com/wps/media/objects/724/741576/chapter_07.html Click on the image to see - not sure if that helps.

Don't kill me if I am wrong - just trying to remember my organic from a year or 2 ago.

 

[virtueixi]

thanks for trying, it was incorrect though.

 

[Ocuflox]

i could answer this question if ur link worked

 

[virtueixi]

Originally posted by: Ocuflox
i could answer this question if ur link worked

It works? THX A BUNCH

 

[Ocuflox]

A= false, there are actually 4 pi molecular orbitals (2 bonding, 2 antibonding)
B= false, there are only 4 pi e-
C=false, it has 3 nodes
D=true, first 2 pi MOs are filled
E=true, it is between C2 and C3
F=true, there is a node between 2 and 3

this is what i would put

 

[Ocuflox]

ill get my friend to look over those answers

 

[virtueixi]

Thank you so much..........I cannot express my gratitude enough. ( It was correct )

 

[dionx]

you arent from uci trying to do online g.chem hw are you?

i remember doing this stuff 4 years ago heh