OCR A Chemistry F324 Rings, Polymers and Analysis Thu 26 Jan 2012

Original post by otrivine

i start and then you give me ok :wink:

what is it called when a mixture is both polarized in light? (1)

o.o Yeah, not a clue. Which exam is this? G494 or G495? :smile:

If it is G494, I've long forgotten that stuff >.<

Reply 1481

otrivine

14

Original post by Oromis263

o.o Yeah, not a clue. Which exam is this? G494 or G495? :smile:

If it is G494, I've long forgotten that stuff >.<

this F324! lool its racemic mixture

my go

Reply 1482

Original post by otrivine

this F324! lool its racemic mixture

my go

Yeah, replace G494 with F324. I don't remember this stuff. Here's a link to my notes for this module - https://sites.google.com/site/mathslab9000/home/chemistry/f324---rings-polymers-and-analysis

Reply 1483

LifeIsGood

12

Original post by Oromis263

You see, it helps to find the A* boundary part :wink:

I purely extrapolated from previous relations in raw mark:ums ratios. Thank you! :smile:

No problem, I was hunting down for it myself for some time now! I thought it didn't exist haha.

Here's the page you can get all the statistics

http://www.ocr.org.uk/administration/results/results_stats/index.aspx

Reply 1484

sorry wrong thread but whoever did the equilibria paper in Jan..any TIPS AND ADVISE please????????? would really appreciate it! i need an A!!! do you find it easier than this rings polymers analysis module?

Reply 1485

otrivine

14

Original post by Raj K

sorry wrong thread but whoever did the equilibria paper in Jan..any TIPS AND ADVISE please????????? would really appreciate it! i need an A!!! do you find it easier than this rings polymers analysis module?

do you want us to ask each other questions?

Reply 1486

LifeIsGood

12

Original post by Raj K

sorry wrong thread but whoever did the equilibria paper in Jan..any TIPS AND ADVISE please????????? would really appreciate it! i need an A!!! do you find it easier than this rings polymers analysis module?

Am doing it in June but what you stuck with??

Reply 1487

hey guys i have a A2 chemistry QUALITATIVE coursework coming up about transition elements..about how to make a complex ion :/ if anyone's already done this can you please give me some advise! just some points to summarise? PLEASEEEEEEE!

Reply 1488

Cath-ay

Original post by Raj K

hey guys i have a A2 chemistry QUALITATIVE coursework coming up about transition elements..about how to make a complex ion :/ if anyone's already done this can you please give me some advise! just some points to summarise? PLEASEEEEEEE!

I'm not allowed to give you precise details, but you can check out the examiner reports>F236>qualitative task in:
www.ocr.org.uk/download/rep_10/ocr_48309_rep_10_gce_jun.pdf
http://www.ocr.org.uk/download/rep_11/ocr_61078_rep_11_gce_june.pdf
If your teacher told you to revise something, make sure you know it well enough to be able to apply it.
Hope this helps, good luck!

Edit: meant f326 not f236 sorry

(edited 11 years ago)

Reply 1489

Original post by Cath-ay

I'm not allowed to give you precise details, but you can check out the examiner reports>F236>qualitative task in:
www.ocr.org.uk/download/rep_10/ocr_48309_rep_10_gce_jun.pdf
http://www.ocr.org.uk/download/rep_11/ocr_61078_rep_11_gce_june.pdf
If your teacher told you to revise something, make sure you know it well enough to be able to apply it.
Hope this helps, good luck!

Aww thanks a lot! (:

Reply 1490

Original post by Abdul100

I done the f325 in january, and i aced it got 150/150 uniform marks.
I found the paper easy as the questions were like the past papers from the previews spec.
If you want to do really good i recommend do all the past papers from the old spec
2002 up to 2012.
The old spec is split into 3 sections which may take a long time to complete but its worth it. Some questions u wont need to answer. Gd luck people

wow! full ums marks? that is sooo good well done! i wish i had your brain :P do you find the rings polymers analysis paper easier too? and thanks for the advice..needed it !!

Reply 1491

Original post by *QueenBeee

Hey guys! Long story short, I have a test tomorrow and my teacher gave us a PowerPoint to revise from. However I've just read something on one of the slides which I Really do not seem to understand!

"solutions of 1 mol.dm-3 with respect to the conc'n of the species involved eg a solution of Cr(VI) in K2Cr2O7 would need to be 0.5mol.dm-3 wrt K2Cr2O7 since 1 mole of solution contains 2 moles of Cr6+ ions."

Does this mean that
1 mole K2Cr2O7----------->>2 moles of Cr6+** AND...
0.5mol.dm-3 K2Cr2O7--------------->>1 mol.dm-3 Cr6+

So if ANYONE can shed any light on the situation, I will be sooooo thankful. I'll major rep u (I know it's nt much, but I'm desperate!)

Thanks! Xx

That is correct. If you think about it in terms of acids (apply the same logic to your problem), you have:

HCl, is a monoprotic acid
H2SO4, a diprotic acid
To get 1 mole of H+ ions, you need to dissolve 1 mole of HCl in solution.
However, to get 1 mol of H+ ions from H2SO4, you only need to dissolve 0.5mole of H2SO4 in solution.

Do you see now? :smile:

Reply 1492

Original post by *QueenBeee

I have another qu! If I have a drawing of a half cell and need to spot the mistakes. The metal rod is manganese && solution is made up of Mn2+, MnO4-, H+ .
Question.....why should the metal rod NOT be manganese??? (it should be inert electrode or platinum wire)

Please help!! Xx

Seems to me like the Mn of the rod may start to affect the relative concentrations of the solutions? I'm yet to re-visit half-cells, so I'm a bit sketchy, but I remember that solutions must be equimolar.

Reply 1493

lagoom

to get an a* do you need 90% on your a2 coursework as well

Reply 1494

Cath-ay

Original post by lagoom

to get an a* do you need 90% on your a2 coursework as well

For an A*, you need to get 90% average (270 ums) across ALL A2 units, inc. coursework work, and 80% average over AS and A2 (480 ums). So it depends on your situation... E.g. You may not need to get a minimum of 90% in the coursework if your unit 4 and 5 ums is high enough to make up the A2 90% average. Hope this helps!

Reply 1495

arvin_infinity

3

Original post by Oromis263

Seems to me like the Mn of the rod may start to affect the relative concentrations of the solutions? I'm yet to re-visit half-cells, so I'm a bit sketchy, but I remember that solutions must be equimolar.

You sure?!

cuz you could have also said copper metal in cu2+ half cell would affect the Cu2+!!

I might be wrong but maybe is something to do with the half-equation given in the question! for example lets say you were given mno4 mn2+ in the half equations you dont want to introduce another element which is not involved in the half equations!
also Mn is more reactive than pt! just a guess!
please someone clarify

Reply 1496