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Chemistry OCR AS Level F322 2014 June QUESTION?!

Hi, I was doing the most recent F322 Chemistry Paper (June 2014)
and came across a mass spec fragmentation question that I can't do.

Compound G is a branched chain organic compound that does NOT have E/Z isomers.
Elemental analysis of Compound G gave the following percentage composition by mass - C-55.8%, H-7% and O-37.2%
Calculate the empirical and molecular formula - I did this and got C2H3O and got C4H6O2 from reading the mass specta which is correct.
However, it's the next part i got stuck on - Write the formula for the particles for Peak X (41) and Peak Y (45) The answer for 41 = C3H5+
and for 45 it's COOH+
But i don't get how this work? can someone explain pls?

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Original post by _Aqsxo
Hi, I was doing the most recent F322 Chemistry Paper (June 2014)
and came across a mass spec fragmentation question that I can't do.

Compound G is a branched chain organic compound that does NOT have E/Z isomers.
Elemental analysis of Compound G gave the following percentage composition by mass - C-55.8%, H-7% and O-37.2%
Calculate the empirical and molecular formula - I did this and got C2H3O and got C4H6O2 from reading the mass specta which is correct.
However, it's the next part i got stuck on - Write the formula for the particles for Peak X (41) and Peak Y (45) The answer for 41 = C3H5+
and for 45 it's COOH+
But i don't get how this work? can someone explain pls?


Yeah I don't really understand it either, the only thing I can think of, is if it were cyclopropanoic acid? However this is a cyclic hydrocarbon, but I don't know if its also considered branched as it has the COOH group branching off it.. its the only thing I can think of that works.. it can't butenoic acid as it has a C=C double bond which will show E/Z isomerism.. if it in theory it was cyclopropanoic acid, CH2CH2CH2COOH the bond between the two carbons in bold would split making a 41 peak of C3H5+ and a 45 peak of COOH+
All I can think of sorry..:')
Also do you have an electronic copy of the 2014 paper? If so could you link it to me as I can't seem to find the june 2014 paper anyway!>:frown:(( thanks
Reply 2
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_Aqsxo
OP
6
Original post by Heffalump .
Yeah I don't really understand it either, the only thing I can think of, is if it were cyclopropanoic acid? However this is a cyclic hydrocarbon, but I don't know if its also considered branched as it has the COOH group branching off it.. its the only thing I can think of that works.. it can't butenoic acid as it has a C=C double bond which will show E/Z isomerism.. if it in theory it was cyclopropanoic acid, CH2CH2CH2COOH the bond between the two carbons in bold would split making a 41 peak of C3H5+ and a 45 peak of COOH+
All I can think of sorry..:')
Also do you have an electronic copy of the 2014 paper? If so could you link it to me as I can't seem to find the june 2014 paper anyway!>:frown:(( thanks


Yeah but doesn't branched mean when there's a carbon coming off another carbon at the top or bottom e.g 2,dibromopropane etc?
I guess i'll ask my teacher.
and no i don't have an electronic copy sorry..
Original post by Heffalump .
Yeah I don't really understand it either, the only thing I can think of, is if it were cyclopropanoic acid? However this is a cyclic hydrocarbon, but I don't know if its also considered branched as it has the COOH group branching off it.. its the only thing I can think of that works.. it can't butenoic acid as it has a C=C double bond which will show E/Z isomerism.. if it in theory it was cyclopropanoic acid, CH2CH2CH2COOH the bond between the two carbons in bold would split making a 41 peak of C3H5+ and a 45 peak of COOH+
All I can think of sorry..:')
Also do you have an electronic copy of the 2014 paper? If so could you link it to me as I can't seem to find the june 2014 paper anyway!>:frown:(( thanks


Hi
Im also looking for the electronic file of that paper but I don't mind pictures taken from the paper. i was wondering if you could take pictures and PM me, i would really appreciate that

Many thanks
Hiya, would you be able to share the F322 2014 paper in whatever format. I'm retaking the exam externally this year so I'd like to use it as practice.


Thanks
Original post by harryheych
Hiya, would you be able to share the F322 2014 paper in whatever format. I'm retaking the exam externally this year so I'd like to use it as practice.


Thanks

Hey, nobody seems to divert their attention towards the need of others. I guess we would have to wait until sometime in may, before the actual exam. Then i will have the paper in my hand.
Original post by Mehrdad jafari
Hey, nobody seems to divert their attention towards the need of others. I guess we would have to wait until sometime in may, before the actual exam. Then i will have the paper in my hand.


Hi there, I agree! I guess so, need all the resources I can find. Cannot afford to do badly again..
Original post by harryheych
Hi there, I agree! I guess so, need all the resources I can find. Cannot afford to do badly again..


Are you doing A2 at the moment?
Original post by Mehrdad jafari
Are you doing A2 at the moment?


Yes!
Original post by harryheych
Yes!


I would suggest you have a look this website for OCR resources.
http://www.stsmith.co.uk/
Original post by Mehrdad jafari
I would suggest you have a look this website for OCR resources.
http://www.stsmith.co.uk/


Wow thanks, I really appreciate it :smile:
Original post by harryheych
Wow thanks, I really appreciate it :smile:


It's ok. Would you let me know when you got the F322 paper? I would be really happy.
Thanks
Original post by Mehrdad jafari
It's ok. Would you let me know when you got the F322 paper? I would be really happy.
Thanks


Yeah, definitely. I would appreciate if you could do the same. :smile:
Reply 13
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_Aqsxo
OP
6
Original post by harryheych
Yeah, definitely. I would appreciate if you could do the same. :smile:


Hi! Sorry, I only just saw this now! I will send both of you pictures of the F322 2014 exam. I wish you both do really well this year also. If you guys want, dm your email and I will send them via that?
Original post by _Aqsxo
Hi! Sorry, I only just saw this now! I will send both of you pictures of the F322 2014 exam. I wish you both do really well this year also. If you guys want, dm your email and I will send them via that?


Thank you so much!!!
Original post by _Aqsxo
Hi! Sorry, I only just saw this now! I will send both of you pictures of the F322 2014 exam. I wish you both do really well this year also. If you guys want, dm your email and I will send them via that?

Hi,
Thanks so much for that, I'm really pleased about that. I also hope the best for your summer exams!
Hi, can someone explain how to do that question please? I don't get it as well :smile: any help would be appreciated
Reply 17
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tinyabs
hi can you also send me one
Reply 18
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Nievahh
4
Original post by _Aqsxo
Hi! Sorry, I only just saw this now! I will send both of you pictures of the F322 2014 exam. I wish you both do really well this year also. If you guys want, dm your email and I will send them via that?


Hi, would you mind sending me the paper too? I'm resitting this exam :smile:

Posted from TSR Mobile
Original post by _Aqsxo
Hi! Sorry, I only just saw this now! I will send both of you pictures of the F322 2014 exam. I wish you both do really well this year also. If you guys want, dm your email and I will send them via that?


hi can you send the question to me as well? all my friends said the 2014 paper was very hard.

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