Read the post below before you read this one.
Ok, Iv'e managed to get a picture up. Basically, the two on the top right show the ring (like my book said), and then the other two show double bonds where the electrons would go instead (which is what my book specifically said wouldn't happen). So does any one have any ideas?
Also, do we need to know anything on halogenoalkanes?
2 comments:
I'm reluctant to respond, Evie, as ideally I'd like others to have an opportunity to read your posts and suggest ideas themselves. However, it doesn't look as if anyone else is blogging this week and I really don't want you to get any more stressed than you already seem to be!
You're absolutely right, both structures are correct and you would get marks in an exam for either structure. The structure with the alternating double and single bonds is called the Kekule structure after the scientist who came up with it. At the time, it was ground-breaking as a number of scientists had tried to discover the structure of the compound with molecular formula C6H6 and Kekule's structure was acknowledged as being a real possibility. Now that further work has been done, the only difference between Kekule's structure and the actual structure of benzene as we know it, is that we now think the fourth electron of each carbon is not 'fixed' in position in a double bond, but spread evenly about the structure, moving constantly. However, Kekule's structure can make it simpler to consider the reactions of benzene as you know exactly where the electrons are at any one time, so that's why you've seen it in textbooks and why it's not considered to be wrong.
Yet again I've rambled on but I hope what I've written has helped and makes sense! See you on Monday.
Forgot to say, you don't need to know anything about halogenoalkanes for this exam. It comes up in one of the topics in the next module that you'll be examined on in June. :)
Post a Comment