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OCR Chemistry Salters B F331 27th May 2016 (Old specification)

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Could you also send it to me too please
I am pretty sure i put +41 as well... can't remember lmao, and yes yes photochemical smog is probably what they wanted, the smoke affect seen by zinc is due to the fact that it will be like particulates in the air
Original post by Kaz_96
These were my calculation answers, in order of how they appeared in the q paper
Mass of air: 834.7
Mass of air for 1g of C4H10O: 11.28
Energy Density: 36200
Hess' Law: +41
KNOW: 34.15%

Not sure if theyre right but lemme know if you got the same/different


literally got the same... i rounded my answers to less significant figures though depending on the question... i found the calculations in this paper very friendly
Original post by smm90
I got the paper if anyone would like a question/marks. Also my chemistry teacher said that they don't take into account the previous years paper at all (he marks for OCR). The boundaries depend on how well everyone does because they set them based on that.


Yeah I thought they do, but considering say last year both AS and A2 retakers sat the exam, so a larger proportion may have gotten lower grade, yet this year it is entirely A2 taking the exam and there's less so the grade boundaries won't be dragged down, and they are more likely to know because they've built on it, I think it'd be unfair but oh well the grade boundaries won't be too crazy
Reply 244
I took pictures on my phone (apologies in advance phone is a bit crappy) - should I just upload them up here as pictures?
Original post by Kira Yagami
I thought if 75% or whatever is Kno3 then 75/mr should give me the percentage of moles ? I dunno

Will i get alteast 1 mark?


you had to almost assume overall 100 percent of the substance is 100g, work out the moles of each different component of the substance using percentage divided by mr. sum of all of these values would give u total moles. then take a percentage of moles of KNO3. hopefully i am making sense
Reply 246
Original post by smm90
I took pictures on my phone (apologies in advance phone is a bit crappy) - should I just upload them up here as pictures?


yes please!!
upload what ?
Original post by smm90
I took pictures on my phone (apologies in advance phone is a bit crappy) - should I just upload them up here as pictures?

Yh that'll be fine!
Reply 250
They were all the right way up... don't know why they've turned and ones not lol
I got all these numbers 🤗🤗 praise Jesus, hard calculations for F331 but if you're okay with maths it was nice
For the energy density I did 1000/74 X 2676 and then I divided the answer by 100 to get 362
for the metallic bonding one,

did you put delocalised electrons for the second box?

It was weird, no?
Wassup fellow retakers :biggrin:,
bit late to the thread buuut some important stuff. Ill get to the important stuff first.

Important?
So i messed up revision for this and was only able to do a few past papers, hoping i'd see a trend, i did the even number years ONLY, so 2012 Jan/Jun and 2014. With my luck, turns out 2016 paper was VERY similar to them three. Not sure if same will apply for further units but its good to know i guess :biggrin:



My thoughts on the paper:
I think i did well on this exam...too well 👀, since ive done this exam twice before, i thought i got an A twice, didnt. But i dunno, im feeling something good about this exam, seems super easy and majority of my answers were the same as others. Im guessing a 47-50 for an A. Theory questions were straight forward, maths were hell.
yea and i think u had tonput charge of ions so it was mg2+ ion and the other one
Original post by Kira Yagami
for the metallic bonding one,

did you put delocalised electrons for the second box?

It was weird, no?


I put sea of delocalised electrons, im sure both are fine.
Okay, it was odd though right?

I mean why not just put some negatively charged particles in or something?

But yeah thanks.
Yeah i see what you mean, they're trying to spice things up for the last paper i guess :P
Reply 259
For the metallic bonding question did you have to put Mg2+ and Al3+? Or could you just write magnesium/aluminium ion, seeing as though the charges were in the diagram that the labels were pointing too

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