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plz help me with this alpha and beta structure of protein.
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plz help me with this alpha and beta structure of protein.
i hope its clearplz can u explain the mechanism in this question 3 c(iii) . i am having trouble understanding it is this thing even in our syllabus ??
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s12_qp_42.pdf
Wa iyyakihttp://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.
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! :/Wa iyyaki
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.
I was just kidding btw But Saudis are a part of my depressing life...i keep wondering what they'll do in the future... jk!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! :/
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.
Actually i know abt this cause my teacher taught us that way...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)
i think it's NH2 instead of NH3...or is it both?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!!!
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 papersRing 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!!!
The amine group basicallyi 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
Both links are the mark scheme. the question?Q1b1
i used MnO4- + 4h+ +3e ... equation
and in ms it uses 8H equation
how to know what to use ??
anyone plz!
http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/Chemistry%20(9701)/9701_w12_qp_42.pdf
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w12_ms_42.pdf
Q1b1
i used MnO4- + 4h+ +3e ... equation
and in ms it uses 8H equation
how to know what to use ??
anyone plz!
http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/Chemistry%20(9701)/9701_w12_qp_42.pdf
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w12_ms_42.pdf
Here's the qp: http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_qp_42.pdfBoth links are the mark scheme. the question?
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