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Reply 1140
Do we need to know what happens in kyoto and montreal protocal???? If so what happens?? Thanks
Reply 1141
Hi,


-CH2CH2CH=CHCH2CH2-


What would be the Z isomer of this ?

No Idea
Can someone pleeeeeeeeeease explain to me how to identify structural Isomers from Mass Spectrometry, Like how do you know which fragment peaks to take and than what do you do with them.

I will seriously love you forever if someone does thankyouuuu
Original post by ray96
Hi,


-CH2CH2CH=CHCH2CH2-


What would be the Z isomer of this ?

No Idea


Maybe this? Excuse my terrible paint drawing
Reply 1144
What do we have to know about the protocols
Original post by ApplePearOrange5297
Can someone pleeeeeeeeeease explain to me how to identify structural Isomers from Mass Spectrometry, Like how do you know which fragment peaks to take and than what do you do with them.

I will seriously love you forever if someone does thankyouuuu


The peaks show you ions, for example a peak at 29 would be CH3CH2+. There may then be another peak at 43 which would be CH3CH2CH2+. There's no calculation to find out what it is you just have to guess by adding different masses. However they usually use 15 (CH3+) , 29 and 43 for a hydrocarbon. The very last peak shows the mr of the whole thing, however if there is a tiny tiny peak after it, ignore the tiny peak. Refer to this image for help about this
mplus1peak.GIF

In the screenshot the m+ peak would be the mr of the final product.

So for example a m+ peak at 58 would be CH3CH2CH2CH3 which is butane.
(edited 10 years ago)
Reply 1146
What do we have to know about the protocols
Original post by Felttip
What do we have to know about the protocols


Nothing really. Justfor example if we get 4/5 marker on green chemistry, just say:

- counties can develop protocols etc

And maybe:
- Kyoto protocol = increased use of renewable energy by 5% by 2012
Original post by theo3335796
Maybe this? Excuse my terrible paint drawing


Yup. That's right!
Say you know the molecular formula of a compound and get given the mass spectrum of it, and the is a fragmentation peak, would it just be a case of trial and error to work it out?


Posted from TSR Mobile
Reply 1150
Original post by niceguy95
Carbon capture storage consists of 2 stages

Co2 is injected deep into the ocean

It react with metal oxides to form stable carbonates

Regarding This topic, it is what scientists do to reduce global warming

Other methods include providing scientifical evidence global warming is occurring to the government

Also following the Kyoto protocol


Btw, they're not two stages of CCS, they're just two types.
Original post by theo3335796
The peaks show you ions, for example a peak at 29 would be CH3CH2+. There may then be another peak at 43 which would be CH3CH2CH2+. There's no calculation to find out what it is you just have to guess by adding different masses. However they usually use 15 (CH3+) , 29 and 43 for a hydrocarbon. The very last peak shows the mr of the whole thing, however if there is a tiny tiny peak after it, ignore the tiny peak. Refer to this image for help about this
mplus1peak.GIF

In the screenshot the m+ peak would be the mr of the final product.

So for example a m+ peak at 58 would be CH3CH2CH2CH3 which is butane.


Ahhh Thank you :smile:

But how would you identify an isomer from the ion peaks? Like this question how do you know from the m/z 29 value, the isomer is butane and not 2methylpropane.image (17).jpg
Original post by needtosucceed=)
did u do f325 in january? we did it as a mock in class and it was killer! same ive got 2 on tuesday :/ are u aiming for an A overall?


i did in january. it was the worst ever score i have gotten in an exam.horrendus.
did u do it?
(edited 10 years ago)
Reply 1153
an someone explain why only two isomers can be formed in Question 4B(iii) - i do not get why only two isomers and not more ? thank you. It the june 2010 paper

http://www.ocr.org.uk/Images/65130-question-paper-unit-f322-chains-energy-and-resources.pdf
Reply 1154
june 2010 paper question 4b iii so confused why only two isomers are formed and not more ?
Original post by motivatedshroom
Thanks for setting up the forum! I just scraped an A on f321 exam with 72/90 UMS points. Very happy it's an A but I wish I scored more UMS points.

Does anyone know the definitions for:
-E/Z isomerism.
-Cis/trans isomerism.

Also I'd be really grateful if someone could please explain the difference. I'm a bit confused. Thanks. :smile:


I missed an A by 2 ums I got 70 :frown:
Original post by ssflcb
june 2010 paper question 4b iii so confused why only two isomers are formed and not more ?


theres no other isomers you can draw..theyre the only 2 possible
Original post by scorpio22
i did in january. it was the worst ever score i have gotten in an exam.horrendus.
did u do it?


nope I did f324 in january, we did the january paper for f325 as a mock in class. Hoping this junes paper should be a lot better considering how bad januarys was
Reply 1158
Is it still possible for me to get an A? I got a high B in unit 1 and a C in all coursework, but I'm retaking F325, F322, and F324
Original post by ApplePearOrange5297
Ahhh Thank you :smile:

But how would you identify an isomer from the ion peaks? Like this question how do you know from the m/z 29 value, the isomer is butane and not 2methylpropane.image (17).jpg


If it was 2 methyl propane you wouldn't get peaks at 15, 29 and 43.
It would be CH3CHCH3CH3 ( 2 methyl propane ) which does not support the absorption's.

For example you may get CH3CHCH2+ which is 42, which is not one of the peaks.

you just have to break it down and look at the individual ions as to what it could be.

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