The Student Room Group

OCR Chemistry F322 June 2016

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Original post by FluffyCommie
Yep! the box at the top are the equations showing how NO catalyses the breakdown on O3, and the structures are the fragment ions I and II from the Mass Spec diagram, both of which i got as well :biggrin: (hopefully we're both right)


On II my plus sign was on the other side... That's the same thing right?
Reply 141
guyyyss who does the unofficial mark schemes normally???
Can anyone remember the initial and maximum temerature of the enthalpy of reaction ?
Anyways what's done is done!!

Prep up for f324 everyone, I wish you all the best of luck! :smile:
Original post by mercuryman
On II my plus sign was on the other side... That's the same thing right?


If you mean you just put the + sign next to the molecule, you MAY get the mark but i'm not sure, it should technically be next to the carbon on the left, but if you put brackets round the fragment ion and then gave it a + charge, that would have been correct i think...
Original post by nicoleemmak
I think I put 1056
I think you would have to times by 3 instead of dividing by 3?
Original post by FluffyCommie
If you mean you just put the + sign next to the molecule, you MAY get the mark but i'm not sure, it should technically be next to the carbon on the left, but if you put brackets round the fragment ion and then gave it a + charge, that would have been correct i think...


I drew it like a carbocation it was next to the carbon for sure, I didn't put a bracket tho?
For the enthalpy change question where you had to use q = m x c x delta T was m equal to 25 ??
Original post by FluffyCommie
If you mean you just put the + sign next to the molecule, you MAY get the mark but i'm not sure, it should technically be next to the carbon on the left, but if you put brackets round the fragment ion and then gave it a + charge, that would have been correct i think...


Besides don't fragments just show at which end carbon lost a bond?

So as long as the fragment adds
Up to m/z
And it has the + indicating it's an positive ion, surely that'd be correct?
Original post by cyborgom
got 14 too :smile:


i got around 14g originally its wrong though...

5/14 *100 doesn't = 45%

I'm pretty sure its around 11g
Original post by student.1997
For the enthalpy change question where you had to use q = m x c x delta T was m equal to 25 ??


Yep the mass was 25
Original post by mercuryman
Hmm I did it another away

(0.0125 x 24.3 ) x 1.25

Giving me 0.380g


It was to 2dp - so 0.38g
Original post by student.1997
For the enthalpy change question where you had to use q = m x c x delta T was m equal to 25 ??


Yes it was :smile:
Original post by Lion2121
i got around 14g originally its wrong though...

5/14 *100 doesn't = 45%

I'm pretty sure its around 11g



Nah trust me it is 14 we both made a mistake dw
Original post by cyborgom
yep i think u do, i got 1 h2c=chch2+ and other one i forgot.


it said it was hex-2-end though, so shouldn't the double bond be on the 2nd carbon?
Original post by getme3as
It was to 2dp - so 0.38g


wtf I didn't notice that why tf was it 1 mark? For all that nonsense
Original post by mercuryman
Besides don't fragments just show at which end carbon lost a bond?

So as long as the fragment adds
Up to m/z
And it has the + indicating it's an positive ion, surely that'd be correct?


Yeah, always next to the one that lost a bond, just so happened that in the drawing it was on the left in both cases...

That would probably get the mark, but for me to be absolutely sure the + sign should be next to the correct carbon.
anyone else mess up the whole of question 7??? i read bromine as oxygen for the empirical formula on 7a so it messed up the whole thing for me, do you reckon its still possible to get an A if i did well in the rest?
Original post by mercuryman
Nah trust me it is 14 we both made a mistake dw


how though?
I did moles was 25/1000 times by 0.5
Then 4.18 x temp change x 25 then did q/moles and got somethjng like -317 anyone else?

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