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Chemistry Paper 4-theory- doubts =D

knowitall10

knowitall10

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AlishaK said:
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w10_qp_41.pdf
@5 -iii) Step 4 AND b) ii .
Q6 ii) just wanna confirm.
I'll so so so thankful to anyone who helps me cause right now I'm some of the worst times of my life with math and chem together. So please asap explain me?!
Jazak Allah Khair!
Cheers.
Click to expand...
Wa iyyaki :D
Don't worry sis. I think all the Saudi dudes have been influenced by the nikammi Saudi society. Even I am sufferring from mini strokes from time to time.
AlishaK and @everyone ImPoRtAnT CoNcEpT!!!!!!
Step 4 is the hydrolysis of the Diazonium salt. An important reaction but not mentioned in our books:
Look at the uploaded photo.
As for b(ii): It gives a white ppt with Br2 and is a disubstituted Benzene derivative- it's a phenol with 2 OH gps:) Tell me if I'm wrong please.
It shows a positive test result with the iodoform test: it has a CH3CO- gp.
 

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AlishaK

AlishaK

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knowitall10 said:
Wa iyyaki :D
Don't worry sis. I think all the Saudi dudes have been influenced by the nikammi Saudi society. Even I am sufferring from mini strokes from time to time.
AlishaK and @everyone ImPoRtAnT CoNcEpT!!!!!!
Step 4 is the hydrolysis of the Diazonium salt. An important reaction but not mentioned in our books:
Look at the uploaded photo.
As for b(ii): It gives a white ppt with Br2 and is a disubstituted Benzene derivative- it's a phenol with 2 OH gps:) Tell me if I'm wrong please.
It shows a positive test result with the iodoform test: it has a CH3CO- gp.
Click to expand...
LOL...what does Saudis have to do with my disastrous-life-right-now? hahaha...Thanks a lot thou. nd yea it ain't in our books! -___-....what's with these brits? Like we'll magically get something we'vent learnt before! :/
 
knowitall10

knowitall10

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AlishaK said:
LOL...what does Saudis have to do with my disastrous-life-right-now? hahaha...Thanks a lot thou. nd yea it ain't in our books! -___-....what's with these brits? Like we'll magically get something we'vent learnt before! :/
Click to expand...
I was just kidding btw:p But Saudis are a part of my depressing life...i keep wondering what they'll do in the future...:p:p jk!;)
Yeah I know, these brits are so vague it's not even funny. But don't worry, if I or anyone finds something that must be known and is not mentioned, InshAllah I'll make sure i tell everyone:):)
 
knowitall10

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Another important concept not mentioned in our books:

For Diazotization and coupling reactions:
Step 1 is the reaction between phenylamine and nitrous acid (nitric (III) acid), HNO2, to give a diazonium salt. This is what we know.
But nitrous acid is unstable and has to be made in a test tube, then the phenyl amine is added:
Nitrous Acid is made using sodium nitrite (sodium nitrate(III)) and dilute HCl:
NaNO2 + HCl ------> HNO2 + NaCl and then, the production of benezene diazonium chloride takes place (which we all know about)
 
knowitall10

knowitall10

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Ring Activating groups (Substitute in the 2,4 and 6 positions): -alkyl, -OH, -NH3
Ring De-activating groups (substitute at the 3 and 5 positions): -COOH, -NO2, -carbonyl, -Cl2

If there're any more anyone wants to add to the list, or if I'm wrong, please do mention it:)
Your help is appreciated!!!
 
HunzaZ

HunzaZ

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Organic
MaxStudentALevel said:
i think we should revise difficult topics in the course! like main points!
BUT organic should be mastered as its a good like 20-30 marks in papers!!
so lets start with revising all organic!!
topics i find confusing are
-Group Trends
-Some calculations
-NMR

:) Any other feedback?[/quot
Yeah organic is a lengthy part.
Click to expand...
 
AlishaK

AlishaK

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knowitall10 said:
Another important concept not mentioned in our books:

For Diazotization and coupling reactions:
Step 1 is the reaction between phenylamine and nitrous acid (nitric (III) acid), HNO2, to give a diazonium salt. This is what we know.
But nitrous acid is unstable and has to be made in a test tube, then the phenyl amine is added:
Nitrous Acid is made using sodium nitrite (sodium nitrate(III)) and dilute HCl:
NaNO2 + HCl ------> HNO2 + NaCl and then, the production of benezene diazonium chloride takes place (which we all know about)
Click to expand...
Actually i know abt this cause my teacher taught us that way...
btw if insm quest they ask for this reaction's reagents and cndtns. do we write HNO2 as the reagent or NANO2/HCL? ! nd thanks a ton! :)
 
AlishaK

AlishaK

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knowitall10 said:
Ring Activating groups (Substitute in the 2,4 and 6 positions): -alkyl, -OH, -NH3
Ring De-activating groups (substitute at the 3 and 5 positions): -COOH, -NO2, -carbonyl, -Cl2

If there're any more anyone wants to add to the list, or if I'm wrong, please do mention it:)
Your help is appreciated!!!
Click to expand...
i think it's NH2 instead of NH3...or is it both?
And also i was taught as: Electron releasing grps (subs at 2,4,6): ch3, -OH, -NH2
electron withdrawing grp(subs at 3,5): -COOH, -NO2, -COCH3
 
1

1357913579

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knowitall10 said:
Ring Activating groups (Substitute in the 2,4 and 6 positions): -alkyl, -OH, -NH3
Ring De-activating groups (substitute at the 3 and 5 positions): -COOH, -NO2, -carbonyl, -Cl2

If there're any more anyone wants to add to the list, or if I'm wrong, please do mention it:)
Your help is appreciated!!!
Click to expand...
thanks alot for your cooperation can u please write the wquation for the reaction which sre the not in the cie book but come in the past papers
:)
 
knowitall10

knowitall10

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AlishaK said:
i think it's NH2 instead of NH3...or is it both?
And also i was taught as: Electron releasing grps (subs at 2,4,6): ch3, -OH, -NH2
electron withdrawing grp(subs at 3,5): -COOH, -NO2, -COCH3
Click to expand...
The amine group basically
 
knowitall10

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Xtremite

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