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NOV12 Chemistry HL - Papers 1 & 2

How did everyone find Papers 1 and 2? I thought that Paper 2 seemed remarkably easy in comparison to other years, and the calculations were rather basic.. I'm not sure how that would translate into the grade boundaries for this year though. Paper 1 was OK, a few strange questions but overall it definitely felt easier than some previous years.

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Yeah, I tend to agree with you there. There were definitely a couple of troublesome questions in paper 1 (16 and 17 i think), but paper 2 was over really quick for me. I found 1 mistake when going over it. So yeah, possibly a higher boundary. Which questions did you choose? I picked 5 and 6, because I don't like redox, and I was sick of organic.

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Haha yeah, Questions 5 and 6 in Section B, enthalpy calculations = less explaining = less marks lost explaining poorly. The one thing I was annoyed with was the buffer calculation (since I'm pretty bad at those), but I had lots of time to work on it. Did anyone else get pH = 4.61?

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Did any do the rate expression question? If so was it 2 and zero order? Very confusing question.

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Yeah, everybody around at my school got pH = 4.61. What were the bond angles in P1 and P2?

P1 I wasn't entirely sure with the SF4 (seesaw/distorted tetrahedral), all I remembered from the textbook was 90,117 and 180.

P2 the first was T-shaped with 2 lone pairs and the second was linear with the three lone pairs, if that's what you are referring to? There were no bond angles necessary though.

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Yeah those are the two questions I'm referring to. For the P1 q, I said 120 and 187; however others at my school have said 103 and 187. For P2 I completely guessed, I said trigonal planar and linear. The problem with revising solely through past papers is that you end up missing out on the recall parts.

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Yeah I was never any good at the VSEPR crap, but for once it was possible to reason the shapes without pure memorization.

Doesn't matter though, human biochem and food chem tomorrow, good luck!

According to wikipedia the correct bond angles for SF4 should be 187 and 101. I'm guessing the 103 option is the closest to 101. I can't even remember which one I chose in the end, but it could be this one :/ haha

Edited by Hus

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what did you guys get for the energy released by 10g of that explosive...? I forgot the complicated name they had for it but i'm guessing that was C4. I think i got something like 77kj which seems huge for just 10 grams...

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what did you guys get for the energy released by 10g of that explosive...? I forgot the complicated name they had for it but i'm guessing that was C4. I think i got something like 77kj which seems huge for just 10 grams...

This was in the energetics section right? Very long and tedious but I also got 77 or so I think.

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I did 4 and 7 for section B lol. Wasn't good with redox but 14 marks worth of one-line answers was just too much of a temptation.

and. ... i got 4.88 for the buffer one, i think. awks.

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I did 4 and 7 for section B lol. Wasn't good with redox but 14 marks worth of one-line answers was just too much of a temptation.

and. ... i got 4.88 for the buffer one, i think. awks.

Yeah I got 4.88 too but the answer is 4.61 :/ When doing the log, you have to do (salt/acid) :( and not the other way round, like I did.

We'll probably get 4 marks out of 5, hopefully!

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Meh. I think for some strange reason I ended up thinking it was - instead of +. 'Cause I had 4.61 and then I changed it when I was checking answers. ggggg

fml.

But yea hopefully everything else went alright. zz

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