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# Chemistry question.. watch

1. I think there's a lot of wrong chemistry in this thread.. Doesn't splitting go by the n+1 rule? So if I had say CH3CH2CH2OCH3, the furthest right carbon is attached to 3 hydrogens, an oxygen and no carbons so according to the n+1 rule there are no hydrogens on an adjacent carbon. n=0. So n+1 = 1. The peak would therefore produce a singlet.
2. (Original post by celinex)
its not really a question! lol.. i just wrote it in my notes and stuck an explanation below it.. (weird i kno..)

In my notes, its says,

When a proton can couple with 3 protons in methyl group, there are 4 alignments of methyl protons that give rise to peaks relative intensities 1 : 3 : 3 : 1

First way: all three aligned with the field
second war: two aligned with the field and one against
thrid way: one aligned with the field and two against
fourthway: all three aligned against the field

i actually have no clue why I stuck it into my notes and i dont understand it!
Ahh okay, yes the relative heights/intensities of the peaks in a signal. It follows pascals triange as stated above

Every electron can be either with (+) or against (-) the field. The possibilities are:
- - -
--+
-+-
+--
-++
+-+
++-
+++

You should be able to see there are two sets of three combos that are effectively the same (pink and oragne) - so the peaks are 3 times higher

Not to be confused with the integration of the peaks, which tells you how many hydrogens that peak corresponds to
3. (Original post by Yellowmonkeyman)
I think there's a lot of wrong chemistry in this thread.. Doesn't splitting go by the n+1 rule? So if I had say CH3CH2CH2OCH3, the furthest right carbon is attached to 3 hydrogens, an oxygen and no carbons so according to the n+1 rule there are no hydrogens on an adjacent carbon. n=0. So n+1 = 1. The peak would therefore produce a singlet.
Yes
4. (Original post by Yellowmonkeyman)
I think there's a lot of wrong chemistry in this thread.. Doesn't splitting go by the n+1 rule? So if I had say CH3CH2CH2OCH3, the furthest right carbon is attached to 3 hydrogens, an oxygen and no carbons so according to the n+1 rule there are no hydrogens on an adjacent carbon. n=0. So n+1 = 1. The peak would therefore produce a singlet.
you will never have a Q like that, the only one you'll get is a CH3CH2 coz it gets way more complicated the more you add on it!
but for that yes the n+1 is the rule
5. (Original post by EierVonSatan)
Ahh okay, yes the relative heights/intensities of the peaks in a signal. It follows pascals triange as stated above

Every electron can be either with (+) or against (-) the field. The possibilities are:
- - -
--+
-+-
+--
-++
+-+
++-
+++

You should be able to see there are two sets of three combos that are effectively the same (pink and oragne) - so the peaks are 3 times higher

Not to be confused with the integration of the peaks, which tells you how many hydrogens that peak corresponds to
thanks.. im just going to go through everything i know and can you tell me if im wrong? and possible vital info ive missed? thanks soo soo much

1. The groups of peaks correspond to the different chemical environments for hydrogen
2. Area under the peaks is proportional to the number of hydrogens in that environment
3. The main peak is split into other peaks by adjacent hydrogens on adjacent carbons. (n+1 rule)
4. The heights/intensities of the peaks.. you look at the number of peaks its split into and use pascals triangle to work them out

(just one question.. in an exam would they ever ask why theres different intensities?)

(thats all i know.. is it enough?)

thanks
6. (Original post by celinex)
thanks.. im just going to go through everything i know and can you tell me if im wrong? and possible vital info ive missed? thanks soo soo much

1. The groups of peaks correspond to the different chemical environments for hydrogen
2. Area under the peaks is proportional to the number of hydrogens in that environment
3. The main peak is split into other peaks by adjacent hydrogens on adjacent carbons. (n+1 rule)
4. The heights/intensities of the peaks.. you look at the number of peaks its split into and use pascals triangle to work them out
I think that covers it

(just one question.. in an exam would they ever ask why theres different intensities?)
Not likely, but it's not impossible
7. (Original post by EierVonSatan)
I think that covers it

Not likely, but it's not impossible
aww thanks soooooo much
do you mind if like i ask you other chemistry quesitons if i have problems?
8. (Original post by celinex)
aww thanks soooooo much
do you mind if like i ask you other chemistry quesitons if i have problems?
Just post your questions up on the forum and I or someone else will try to help
9. EierVonSatan has a PhD in chemistry

Your going to be my chemistry bible for the next 5 months. I have crappy teachers.

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