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AQA CHEM1: 15th May 2012

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For the relative atomic mass, I got 85.6

For the equation which makes BCl3, I got B + 1.5Cl2 --> BCl3

For all of the calculations near the end, I got:
1) 2.81 g
2) 2.21 moldm^-3
3) 8.98% or something like that
4) B2Cl4

I mucked up that equation near the end about sodium borate. What was that about :confused:

And was it just me, or ws there waayy too much on bonding? Not much electronegativity, hydrogen bonding, nothing on catalytic converters, not much on shapes..

On the whole, there was lots of calculations and explaining high melting points etc. And some on periodicity and organic chem. I found it okayish, harder than usual though

Hopefully grade boundaries are low :smile:

(edited 11 years ago)

Reply 541

Abbieastoria

I had absolutely no idea for the reagent so I just put h2o :/

Did you put the use of Y as camping fuel?

Reply 542

sososososxc

what was the electronic configuration ?

any1 got the paper?

Original post by berryripple

How many marks will I get for dividing by 6 instead of 5 in the gas calculation if I did everything else correctly?

Probs 3/5 because you'll get one for rearranging the equation, one for putting te right numbers in and one for Timsing moles by Mr to get mass.
I forgot to divide it at all! I got a bit carried away. Oh well :frown:

Reply 545

Mystic Creature

Original post by Abbieastoria

I had absolutely no idea for the reagent so I just put h2o :/

Did you put the use of Y as camping fuel?

Hmm I wrote just h2, but i think it's h2so4

And erm, i just wrote 'fuel' lol, hopefully they accept that :colondollar:

Reply 546

Millyshyn

Original post by Abbieastoria

I had absolutely no idea for the reagent so I just put h2o :/

Did you put the use of Y as camping fuel?

I got the reagent as H2 ;o and for Y I had no idea, just put Petrol.

Reply 547

neeloo

Original post by jodiedoodles

Aaah I put titanium was hexagonal close packed structure, as it said it had bonding similar to magnesium which is hexagonal close packed :frown:

Magnesium is metallic too? positive ions surrounded by a see of delocaliused electrons? Im sure its graphite which is arranged into hexagonal layers not magnesium with vdv forces holding the sheets together.

Reply 548

lochbeau

Original post by Philippamalko

for the 14.06g one did you not divide the number of moles found with pv=nrt by 5 as it was the moles for all the gases produced (5 molecules) and use that to find out the mass? i got around 14g the first time then read the question again and got around 2g or something

Was probably my mistake then, hopefully 3 or 4 out of 5 for method?

Reply 549

Pinkhead

Original post by Abbieastoria

I had absolutely no idea for the reagent so I just put h2o :/

Did you put the use of Y as camping fuel?

I put H2S04 for that one.
And i'm pretty sure it is a (camping) fuel, although I didn't write that myself. I was a bit of an idiot and just wrote 'used to make polymers' lol.
Wasn't thinking straight.

Reply 550

mulac1

Well, I thought that was without doubt the hardest unit 1 test from all the past papers. Clearly there has been a massive change from before the Jan paper, in terms of difficulty of the test. The formula for sodium borate is Na2B4O7... Lets be honest ... who got lucky?

Reply 551

Philippamalko

what do you think the grade boundary for an A will be on this exam?

Reply 552

mulac1

and i think the reagent was H2... yes ok you could get it using common knowledge but even so, the reaction to go from alkenes to alkanes is not on the unit 1 syllabus!!!
I think it's like when you harden vegetable oils (or somin like that)...

Reply 553

jodiedoodles

Original post by neeloo

Oh dear

I thought graphite was giant covalent (macromolecular) structure, and zinc and magnesium had a hexagonal close packed structure? :frown:

Reply 554

AishaTara

Original post by berryripple

It's a shame that this unit, the easier one, is worth less than the disgustingly difficult one :frown:

well thats why its worth less, as its easier.

Reply 555

Mozzatron93

Original post by Mystic Creature

Hmm I wrote just h2, but i think it's h2so4

And erm, i just wrote 'fuel' lol, hopefully they accept that :colondollar:

It is H2, its just hydrogenation!

Reply 556

Abbieastoria

For the concentration question I did have 2.21 but then I realised the question said that the volume was 500cm3 of solution, not of hcl. So I divided 500 by 4 then timsed by 3 as it was a 3:1 ratio and got 2.95

But everyone seems to have put 2.21 I just stop thinking so much and go with my initial answer. What a nightmare

Reply 557

Millyshyn

Original post by mulac1

How the hell was anyone supposed to know the formula of it?! lol!

Reply 558

mulac1

it was 53/70 for an a in jan, and i'd say this exam was about the same difficulty if not harder. I think it all depends on how generous they are on those long answer moles calculations in terms of marks for working.