Equilibria, Energetics and Elements (F325) - June 2011 Exam.

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Off the top of my head:

+Magic tang.
+The KOH decomposing at the terminals.
+Determining change in enthalpy from.. well no values.
+Polymer bidentate complex ions??

I'd need to see the paper again to bring up all the ones I thought 'WTF IS OCR DOING??' questions.

magic tang was just the way they dressed up a buffer solution problem, nothing beyond our scope.
the polymer and enthalpy questions were synoptic and application of knowledge, and 20% of the paper is supposed to be synoptic.
the KOH is application of knowledge, and it was only a 'suggest' question, meaning there will more than likely be more than 1 accepted answer. stop whining, we all sat the same paper. complaining won't do anything - every year they scale the raw marks depending on how many people got whatever mark so the top 20% get an A, or whatever.

Reply 2601

MoTheMedic

Original post by BackDoorEntry

I'd prefer a memory test but sadly its all about application.

+Magic tang was applying knowledge of buffers and the relation of pKa and pH to an unknown situation. The question didn't ask what is magic tang.
+Ice melts when you heat it, thus deltaH is endothermic?
+ That is an A* synoptic question designed for those people who want an A* to prove they know what they're doing.

Reply 2602

Andygunner93

Original post by CrazyDaisy123

You know the buffers question.
Did you have to use one of the acid in the question?
... i rambled on about ethanoic acid :frown:

And what was the neutralisation ans?

It doesn't matter which acid you picked. I chose ethanoic as well

which neutralisation question?

Reply 2603

Hydro.ZX

Original post by Sereni

Pretty sure I have an A... I ****ed up by not multiplying the Cl- hydration by two, getting 2.27% for the percentage of copper, and some of the other weird questions. I didn't drop more than 20 marks though...

feelsgoodman

Reply 2604

Sereni

Original post by arvin_infinity

Those people who think they have done well on this shocking paper (Hahahah u must be joking ! )
If u actually have done well..let us know how
Am really curious even if I'd known its gonna be this weird crappy paper I probably wouldnt have been able to prepare for it!! Did so many pastpapers but it was not any similar whatsoever

Think i dropped 8 marks on the last question, three on the electrode decomposing one and the ligand polymer question. Other than that i found it quite an easy paper

Reply 2605

BackDoorEntry

Original post by Sereni

Magic tang was 1 mark and it was just that acids are siur i think, koh i agree no clue, i managed to work out change in enthalpy with whatever they gave us (cant remember) so it cant have been impossible, and the polymer bidentate one was really just application of knowledge, you know it canform two coordinate bonds, you know the formula, you should be able to guess what its like, i think i screwed that one up coz of lack of time but i figured it out as i was leaving the exam

Magic tang was one mark? Wasnt it a large structured question? I had to keep on reading it to see if there was anything I missed!

None of it is impossible, but for an A level exam, some crucial bits were unecessary, and somewhat distant from the specification... which is just not on.

Reply 2606

BA1

The polymer should have been drawn similar to this (but obviously with Nickel instead of Silver)

Reply 2607

Teva

Does anyone know the equations for NiCd battery when recharging??
and the ionic equations at the negative and positive electrodes making hydrogen and oxygen...was it in a KOH fuel cell... or something??

(edited 12 years ago)

Reply 2608

Vinchenko

Original post by BackDoorEntry

magic tang - agreed!
KOH - agreed, ridiculous! even my chemistry teacher was confused by that...
enthalpy change - which one?
bidentate ligands - thought that wasn't a BAD question, since it's a straight extension of work that's in the textbook and on the syllabus, though the drawing of the polymer was NOT worth enough marks.

Reply 2609

RealisticDeity

Original post by Hydro.ZX

Everyone has been getting like 67% on that question, and I got like 3% so if you got 2.27%, i feel a little better about that!

Reply 2610

susan23

Original post by wiseman93

Original post by susan23

Dont bother complainign to OCR they wont change much...
complain to these guys [email protected] are the people who assess these exam baords

These are the people who I presume will regulate the examining bodies like OCR and make sure they don't blindside their candidates like this again right?

Well that's just dandy but I could really care less about future papers being fair and I'll be done with a-levels in a week or so so yeah not trying to sound selfish here but I think we should put our energy in complaining towards whoever will actually lower the grade boundaries accordingly.. OCR!!!

Quoted from http://www.ofqual.gov.uk/

It is our duty to ensure all learners get the results they deserve and that their qualifications are correctly valued and understood, now and in the future.

(edited 12 years ago)

Reply 2611

Vinchenko

Original post by BA1

The polymer should have been drawn similar to this (but obviously with Nickel instead of Silver)

Er...but the square brackets would surely be outside the rest of it? but otherwise, agreed.

Reply 2612

katelv

Original post by Sceaga

k=0.00342?? anyone else get something like this

I got same result for k

Reply 2613

susan23

Original post by BA1

The polymer should have been drawn similar to this (but obviously with Nickel instead of Silver)

that looks like a ****ing alien hand

Reply 2614

BackDoorEntry

Original post by MoTheMedic

Okay I agree with the first point. I guess the way I saw it was a bit different because it simply took a lot out of me to actually find out what the question was asking of me!

Second point, didn't the question just say that it melts at 0 degrees, no mention of heating it. I put endothermic anyway.

For the third point.. How on earth do you prepare for a question like that though? I did some extra reading, i visited content from other specifications, I read deeper into topics we covered. Getting those A* questions right are just too hard to bother with, with hindsight!

(edited 12 years ago)

Reply 2615

Vinchenko

Original post by Teva

It's the opposite way around to the way that ought to be feasible, since you are putting energy in not getting it out. So essentially the equilibira just lie to the other side they did in the first part, the discharging question. I realise this AFTERWARDS..

Reply 2616

mitch1234

Original post by BA1

The polymer should have been drawn similar to this (but obviously with Nickel instead of Silver)

i did this but split the molecule so one ring coming off as each ligand. basically the same thing but moved over to the right a bit if you know what i mean?

Reply 2617

bigAsh

I'm desperate to see the paper! I want peace of mind :frown:

33.8%

Original post by BackDoorEntry

Oh i assumed that ppl were refering to the last bit of it comment on the prediction that the magic tang is due to ph, the rest of the question was standard stuff about juggling around ka pka ph and h and ****. I guess my only big problem was time pressure, give me another ten minuted and i probably couldnt finished and gone back to figure out the polymer question

To the guy asking about rechargeing you just went backwards in the full equation, basically reversing the reaction which happens when the battery discharges