OCR AS - Chemistry Unit F322 - Chains, energy and resource - REVISION!

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For the last question, did you actually have to draw the structures? I swear it just said to identify the compounds, there didn't seem to be any explicit mention of drawing the structures in the question from what I remember, anyone able to clarify?

"Identify" is probably just displayed, structural, skeletal, molecular formula etc.

I suppose as long as you don't draw one thing and write another it should be alright. We had an almost identical question as a mock test and they allowed structural OR displayed OR named etc. I think :biggrin:

Reply 801

UnbreakableDimmy

Original post by Kir4nK

wiki is not always right lol ?

Honestly, at that point it becomes so obscure no one is going to bother putting rubbish down.

Reply 802

yu80359

god dame I wrote the right structure for X and wrong name for X do I lost two marks ?

(edited 12 years ago)

Reply 803

racheatworld

Original post by bagelbe

Really? Because I drew the structure right, but put methyl ethanoate??? :/

Yes, if you drew the ester correctly, but put the wrong name for it, you'll lose the marks.
I did the same thing on a practice paper but for phosphoric acid, I wrote out "phosphoric acid" but then put the wrong formula for it, as my teacher said this counter-acts the mark I got. It's the same with drawing and naming, because the examiner doesn't know which is your answer, so assumes it's wrong.

Reply 804

UnbreakableDimmy

Original post by Joseppea

I did the same paper, except at home instead of school. I found this one harder though, but at least I've got the majority of the marks!

Reply 805

DoDoBeDo

I wish I never said I wanted a question on green Chemistry. <_< ARGH. I think I did okay. I wanted an A but, meh, not feeling so confident now :frown:

I think I'd be lucky to get a C on that paper :frown:

My heart is actually broken because the past papers I was getting 90% on - this paper was just so different to past papers! :frown:

& It's not through not revising the green chemistry, because I did, I had a feeling it'd be heavy but not as heavy as it was :frown:

Argh. Not happy. Now just wait until August 18th to see how spectacularly I ballsed it up :frown:

Reply 806

SmithytheDrummer

Original post by DeanFoley

Don't worry too much about it. I've done quite a few past papers on these, and the last one I did, an A required 77 marks. The others were all lower, from 72-75!

There is quite a bit you can afford to expend, even on silly things. I made many myself!

Just out of interest, what did you put for the international cooperation one, and the one about dynamic equilibrium in a car?

Reply 807

bagelbe

Original post by racheatworld

nooooooooo :frown:

I think I got the other two right though? But the empirical formula didn't agree with the m/z value so I just worked it out from the m/z value because I go into a bit of a panic :L

Reply 808

conzag123

Original post by abercrombie_gal

i thought atom economy is more important because the process is more sustainable because i came across a question just like that in a past paper...all in all, i think its a good paper for a person to retake

I wasnt sure about this question at all and left it until the very end to think over it..... I was tempted to write down what you wrote as I too have seen this in a past paper. however, as it was to do with fermentation (i hope that's what the question was referring to now i think of it), i said the atom economy will always be the same as co2 will always be produced as the reaction is very specific to the zymase enzyme found in yeast so percentage yield is more important so you can make more ethanol, considering co2 is always going to be produced.

it was one of those "i dont really know what im writing" type of answers but i thought it made sense when i read what i'd written :biggrin:

anyone want to comfort me and tell me if this will get any marks??? didnt it say what do you think is most important, so you could put eiter as long as it was justified???? (not sure tbh) :smile:

Reply 809

kimmey

i put in a car there is no closed system ?

Reply 810

UnbreakableDimmy

Original post by SmithytheDrummer

Just out of interest, what did you put for the international cooperation one, and the one about dynamic equilibrium in a car?

In intenational co-operation, I put that because waste plastics can travel across national boundries in the ocean etc, it was important nations co-operated to dispose of them.

For dynamic equilibrium, I put because there was a constant influx of gases and they were constantly being expelled out the exhaust pipe.

Reply 811

Joseppea

Original post by kimmey

i put in a car there is no closed system ?

I just put that they weren't in the exhaust long enough :lolwut:

Reply 812

conzag123

Original post by kimmey

i put in a car there is no closed system ?

yes me tooo :d

Reply 813

Kir4nK

can anyone predict what the grade boundaries are likely to beeeee?

Reply 814

UnbreakableDimmy

Original post by Joseppea

I just put that they weren't in the exhaust long enough :lolwut:

Wouldn't exhaust be where they leave anyway :P?

Reply 815

demesto

i put insufficient oxygen supply

Reply 816

nereik6794

Original post by Joseppea

I just put that they weren't in the exhaust long enough :lolwut:

I wrote about the catalytic converter haha. Only 1 mark though

Reply 817

bagelbe

Original post by Joseppea

I just put that they weren't in the exhaust long enough :lolwut:

I put that there was not enough products??? :/

Reply 818

UnbreakableDimmy

Original post by Kir4nK

can anyone predict what the grade boundaries are likely to beeeee?

Really, no one can do that. It just depends on the results nationally. If we took an average of past paper grade boundries, about 75, but they've gone as low as 72.