AQA CHEM5 A2 Chemistry - 19th June 2013

hi what did everyone get for the q=mcdt question, i got 503k

also on the last question i got a 2:1 ratio, how did people get 3:1?

Didn't you use the AQA official book for chemistry? Moreover it said you need to know and understand ▲E=hV

yeah i thought 503 was a bit big but i didn't know what to use for q

**** off

Cant you just put up the whole paper??

For question 4e it was the reaction of phosphorous oxide with NaOH not MgO .

Ok. Looking at that mark scheme and all of the previous year's grade boundaries, I have got a D when I was aiming for an A. Completely messed up that exam. So angry with myself. How was I supposed to know the unit of frequency. That's not general knowledge and Ive never been taught that. Grrrrrrrr

i put cocl3nh3 but i put a negative charge because technically that would be the charge but then that makes in an ion so i'm unsure, but if cocl2nh3 is neutral cocl3nh3 is -1? any thoughts mate?

true dat i wrote 6NaOH+ P2O5--------->2Na3(PO4) +3H2O

Same :'( 52 based on the unofficial mark scheme! I did something stupid on every calculation question, mucked up a few equations plus got some of the explainy ones wrong

I know how u feel but remember the unoffical MS is missing two questions. I needed a high B to get my overall A and i dont think i've got it

Well no because its asking about lattice dissociation, which is endothermic, so would increase, and no because the additional strength of covalent character with the ionic lattice means there needs to be more energy to overcome these forces, the only exception of this rule however, for a very complicated reason is Al2O3

See I didn't notice the part where it formed a solid, so I didn't have any bones about putting the charge. However knowing it was a solid, I am a bit confused by the whole question.

The ratio was 3:1 definitely, but with nitrogen, chlorine, cobalt and hydrogen only, I don't see how you can make it not having a charge :-/ im just praying for low boundaries.

Well no because its asking about lattice dissociation, which is endothermic, so would increase, and no because the additional strength of covalent character with the ionic lattice means there needs to be more energy to overcome these forces, the only exception of this rule however, for a very complicated reason is Al2O3

It said it was prepared with an oxidising agent so I think the Co²⁺ was oxidised to Co³⁺ so there was 3 Cl^- in the complex to form a ppt? I'm really unsure about the complex though, I rushed this one

This paper was very tricky no doubt, and not all the questions were accessible to all candidates. Let's take an example, the 2 marker on the y=mx+c, which is although seen as simple, is a maths derived question with Math students having an advantage over those who don't even study it at A level. I forgot all that stuff from GCSE but yes I understand it was an application based Q but still y=mx+c isn't exactly on the spec. Also at college, we were told derivation of delta G was not required.

Also the synoptic 5 marker was a bummer. The last question was difficult
and I haven't seen a Q like that before either - although some people found it ok.

A paper which is normally accessible to all candidates was turned upside down and its fair to say CHEM5 could have potentially caused a majority of us to slip up by a grade due to their inability to ask bloody straight forward Q's, so annoyed... Like the majority ��


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