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Author Topic: What are the pi and sigma bond structures in benzene and other organics?  (Read 17718 times)

Offline omid

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can you please tell me the structures of pi and sigma bonds in ethane, methane, ethene, benzeneand chloroethane? :o
« Last Edit: 26/05/2009 14:05:50 by chris »


 

Offline Chemistry4me

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Methane and ethane are sp3 hybrisised, no pi bonds.
Ethene is sp2 hybridised, 1 pi bond, the rest sigma.
Benzene is sp2 hybridised and each carbon has a p orbital. All six are defined as equivalent, so it's impossible to define three localised alkene pi bonds. Each p orbital overlaps well with both neighbouring p orbitals, resulting in two doughnut-shaped clouds.
 

Offline omid

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chemistry
« Reply #2 on: 29/05/2009 13:19:28 »
can you please tell me the structures of pi and sigma bonds in ethane, methane, ethene, benzeneand chloroethane?
 

Offline Chemistry4me

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« Reply #3 on: 29/05/2009 23:20:13 »
Why don't you just tell me what you do not understand about my answer to the question and we'll go from there. I think that way you might actually learn something instead of just asking for the answer. :)
 

Offline omid

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« Reply #4 on: 30/05/2009 16:50:52 »
look please don't be angry :(.
you did not read my question carefully i need drawn structures of ethane, methane, ethene, benzeneand chloroethane which mentions pi and sigma bonds in them?
if you can please provide me with some accurate sources of information or you can just tell me the drawn structures of them.
thank you
 

Offline BenV

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« Reply #5 on: 30/05/2009 17:25:44 »
I've merged these two identical topics - please keep all discussion of one topic to one thread.

Also, if I may express an opinion - you didn't ask for drawn structures before, so you can hardly blame Chemistry4me's reading skills if you didn't get the answer you were after.
 

Offline Variola

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Also try doing some of the work yourself.... drawing the structures out etc and trying to figure out where the bonds would be. The structures of the chemicals will be available in any good chem book or online.
Then when you have done that, if you are still stuck them come back and ask for help on specific points rather than just expeting the answer.
It's what I and others have to do.
 

Offline omid

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i've been doing this myself for past two weeks i didnt find anything thats when i joined the science forum and asked for help.
if you dont have the answer then i must say that this topic is not for you and you better stay out of this topic.
 

Offline Variola

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Quote
if you dont have the answer then i must say that this topic is not for you and you better stay out of this topic.

Actually I do have the answer as I am currently revising for my chem exam, chemistry is not a science that comes easy to me so I have had to draw out all the structures of the chemicals and compounds I have been looking at... hence I know that the answers are out there if you bother looking for them.
Do some of it yourself and people will be far more inclined to help you, rather than just give you the answers.
 

Offline omid

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look if you don't want to answer my question then please don't bother yourself
infact the time you are using to reply me why don't you use the time to prepare for your chem exam.
and by the way my question was for chemistry4me so just let him reply.
thank you for your help again.
 

Offline Variola

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look if you don't want to answer my question then please don't bother yourself
infact the time you are using to reply me why don't you use the time to prepare for your chem exam.
and by the way my question was for chemistry4me so just let him reply.
thank you for your help again.

Why dont you take the time you are spending on here demanding answers to try and do he work for yourself, and I respectfully suggest that it is you who needs to do their revison and not me. C4M has already given you an answer that would enable you to draw it out, people are not here just for your benefit.  ::) ::)

Gee how many times can you tell someone!!  ::) I think I'll give up now.
 

Offline omid

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good for you
 

Offline Chemistry4me

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I don't know what structure you are after, does it look like:

b)



OR

is it like:

 

Offline Chemistry4me

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You know what? I think you are after the latter in which case:

Ethane



Benzene



Ethene



Chloroethane



« Last Edit: 31/05/2009 00:15:26 by Chemistry4me »
 

Offline omid

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thank you
i think the first one is what i m looking for.
thank youuuuuuuuuuuuuuuuuuuuuuu ;D
 

Offline omid

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My qustion is for chemistry4me
can you please tell me the question below;
evaluate the influence of structure and bonding on the course of reaction and explain the follwing;
alkanes undergo free redical reaction.
what i dont understand in this question is the that the word evaluate is confusing me that's why i dont understand that what the question is really asking for??????????????????????
 

Offline Chemistry4me

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I think it is asking you to explain why the structure and bonding in alkanes (are you sure it is alkanes and not alkenes?) causes it to undergo free radical reaction.
 

Offline omid

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thnx again
yh it is alkAne

                                                                                                                                                                                                                 
 

Offline omid

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One more thing can you help me with biology topics as well please.
 

Offline Chemistry4me

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Haha, post it and I'll have a look. But I make no guarantees.
 

Offline omid

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My question is explain negative feedback in homeostasis using example in the human body?
I am considering using the link below;
if you can please check and tell me if i am on the right track
http://science.jrank.org/pages/3365/Homeostasis.html
please help me out My tutor is a big monster hes going to kill me if I did not do it accurately. Even today he was like shouting at me saying that he needs it by the end of this week.
 

Offline Variola

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That link is fine for explaining the basics, but it depends on how much depth your tutor wants you to go into?
If its just a short question then it should be fine, if its longer you might want to use more specific examples of negative feedback loops, glucose metabolism is problably the easiest one to use, or you could use the blood pressure one in the link but that canget a bit more complicated as parts of it can involve pH levels.

EDIT:

http://bcs.whfreeman.com/thelifewire/content/chp50/5002002.html

Thats got a nice animation on it to play with and is well explained.
« Last Edit: 03/06/2009 10:00:09 by Variola »
 

Offline Chemistry4me

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Haha, I didn't even see omid's last post.
 

Offline Variola

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Haha, I didn't even see omid's last post.

I have a biology radar.... anything biology related blips up on  my screen..:)
 

Offline Chemistry4me

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Yeah? Can you help me with RNA transcription? Or is that DNA? :)
 

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