IGCSE/GCSE/O & A Level/IB/University Student Forum
Qualification => Subject Doubts => GCE AS & A2 Level => Sciences => Topic started by: Deadly_king on August 01, 2010, 11:18:34 am
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salaam every1.......
well...........i ws luking through my notes when i discovered something lacking.................i then consulted the text books but there ws nothing abt that there 2.
Guess i'll try my luck here.... :)
Its abt halogenoalkanes.....................it is said that they undergo nucleophilic substitution reaction.
However primary halogenoalkanes undergo SN2 mechanism while tertiary ones undergo SN mechanism............bt wat abt secondary halogenoalkanes???
Does any1 have a clue???
if yess, plz let me knw
feel free 2 leave ur comments, opinions, advice n tips ;D
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http://www.chemguide.co.uk/mechanisms/nucsub/whatis.html
This will clear your doubts :)
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hey thanks dr...........it really helped me :)
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Hmm...........I don't know if it's mentioned in the syllabus but i've got a question in a 2007 paper. So I just thought of clearing my doubts with your help.
Nitration of benzene requires concentrated nitric acid as reagents.
Conditions : Temperature < 60oC and Concentrated Sulfuric acid as catalyst.
However for the nitration of a phenol same conditions are applied except that dilute nitric acid is used.
Anyone has the slightest idea??
Is it because phenol carries an electronegative oxygen atom on one of its carbon atom which withdraws the electron clouds towards itself. Hence the other carbon atom develop a partial positive charge which allows it to substitute a hydrogen atom for a NO2 electrophile.
Can anyone confirm if my theory is correct??
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The OH group is electron releasing. It increases the electron density of the delocalised system, making substitution much easier compared to benzene
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The OH group is electron releasing. It increases the electron density of the delocalised system, making substitution much easier compared to benzene
Yeah............I've already figured it out though :P
Anyway thanks for your help :)
+rep Ahana ;)
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Garfield. Call me Garfield yea? :P
You're welcome :)
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Garfield. Call me Garfield yea? :P
You're welcome :)
Ok......no need to get upset.
I was just teasing you ;)
Seems you like the lazy cat Miss Garfield? :p
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Ok......no need to get upset.
I was just teasing you ;)
Seems you like the lazy cat Miss Garfield? :p
I ain't upset mate.. :D
I am Garfield. ::)
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I ain't upset mate.. :D
I am Garfield. ::)
It's funny..........It just crossed my mind that you were actually kidding! :P
Unlike your signature. ;D
One thing is sure though..................you are not as lazy as Garfield ;)
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HAHAHA... :D
I'm NOT lazy? Say that again :P
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HAHAHA... :D
I'm NOT lazy? Say that again :P
Well at least not on the forum ;)
Since you are always ready and available to help anyone. Am sure it's not a coincidence that you have been elected administrator. You must have been very hardworking and dedicated to your task :)
By the way.......can you please check this for me :
https://studentforums.biz/sciences-149/question-related-to-free-radical-mechanism/
Its June 2010 P12 No 27....CIE. It is about dehydration of alcohols to form alkenes.(Third post of the thread)
Am not very sure about the answer........... :-\