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Aqa chem 4/ chem 5 june 2016 thread

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Original post by chloeabeki
I put: D 1st, E 2nd


Me too! Thank god I was so sure D as 1st order was wrong!!
Well, that was great.

Great as in let me just bury my soul then proceed to dig myself back up for tomorrow's S1 exam.
Original post by Powpao
Did anyone get 1st and 2nd order for the rate equation question. The numbers were so awkward.

I did 😁
Original post by thehollowcrown
i thought that the acyl forms the white ppt, not the haloalkane


Yeh acyl as faster reaction cholro alkane takes longer
Reply 824
Original post by AliRock
Can't be, it said it reacted to form a green solution with acidified potassium dichromate (VI) so it can't be a tertiary alcohol.
But what I did get was similar: CH3 - O - C (CH3)2 - CH2 CH2 OH


wasn't the OH a singlet? In this case it would be a triplet. Not sure tho..
They normally accept a range of answers for reagents.

For the acid (acyl) chloride the simplest (in my opinion) was:

Reagent: AgNO3
P: no visible change
Q: white ppt (of AgCl)
Original post by latinken
What did you get for number of carbon peaks?


9 but I didn't have time to check so it's probably wrong
Original post by ASLEVELSHELPME
A* - 7/100
please...


Please, I'm currently on 7!
Original post by yung7up
Hmm any tips on how to prepare for mcdonalds interview and any resources? Thanks in advance


Omg that made my day haha...

prospective Uni degree to working at the drive thru mcdonalds
Original post by t0310
AgNO3 does react with acyl cholrides tho[/QUOTcr

NOOOO I MEANT TO PUT AGNH3
Original post by SirRaza97
Do you think Ni/H+ in ether will be right as well for step 4?


This is an extract from a previous mark scheme. And it shows what they accept for both steps.

(edited 7 years ago)
Original post by ASLEVELSHELPME
A* - 7/100
please...


fingers crossed
Original post by latinken
What did you get for number of carbon peaks?

9 peaks???
0 and 2 for rate
i said to make the ester into sodium ethanoate, you had to add water and h+ catalyst to break it up then naoh, then chromatograpy
Original post by SirRaza97
No I don't think so, feelsbadman


Fairly sure the reagent was Na2CO3 man
So which Donny is doing the mark scheme?
Original post by thomaarrss
what did everyone out for Ka for a strong acid, i put it fully dissociates so a not needed, didn't know what to put for second mark??


Yeah fully dissociates, Ka would be infinite (you would be dividing by 0)
Reply 838
Original post by Bacardigan
Anyone know what happens to the rate equation if the experiment was repeated with 100x the concentration of ethanal but same concentrations of HCl and Iodine? I put that it would be the same...


I said the rate equation becomes
rate=k[H+] because the propanone concentration is so high that it becomes constant


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Original post by girl :D
i wrote the same reagent but i wrote effervescence for acyl chloride

I think it could be either as its kind of the same, maybe ?

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