The Student Room Group
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>

OCR A2 CHEMISTRY F324 and F325- 14th and 22nd June 2016- OFFICIAL THREAD

Scroll to see replies

I have added all the grade boundaries for A/A* and calculated averages

http://www.thestudentroom.co.uk/showthread.php?t=4180862#primary_content

bring more voters! :biggrin:
Original post by steph-carys
Can't quite remember what I did, I think maybe I did HYD + HYD +SOL= LE so it was probably just a sign problem? :tongue: hopefully I will still get some marks


Yeah I just looked in the textbook and i think i get the problem, I drew that extra line with the hydrated ions on it below the line with the actual solid on it but i think it was supposed to be above it, not sure how you were supposed to know that though
Original post by a209150


Can't be right as H+ would appear in rate eqn
Reply 3663
Avatar for Jm098
Jm098
2
i put h+ is not regenerated is that enough?
Original post by Jm098
like copper sulphate and it forms sulphuric acid and cu(hcoo)2


lol i put Cu(OH)2 to form Cu(HCOO)2 and H2O....no idea if that counts :/
Original post by smartalan73
Yeah I just looked in the textbook and i think i get the problem, I drew that extra line with the hydrated ions on it below the line with the actual solid on it but i think it was supposed to be above it, not sure how you were supposed to know that though


I managed to draw my born haber cycle correctly (I think) so I have no idea why I calculated the terms in the wrong order.... again I'm gonna blame the person playing the drums next door.... pffffffftt.
The rate equation thing is:

I- + H2O2 => H2O + IO-

H+ + IO- => HIO

HIO + I- => I2 + OH-

OH- + H+ => H2O




Posted from TSR Mobile
Were there any equations or compounds (except the ionic equation on the last page) where it was necessary to put state symbols?
Original post by smileez_101
lol i put Cu(OH)2 to form Cu(HCOO)2 and H2O....no idea if that counts :/


So did I, it's fine because you'd be reacting an acid and an alkali, getting a salt (Cu(HCOO)2) and water.


Posted from TSR Mobile
Original post by MrZebraCookie
Were there any equations or compounds (except the ionic equation on the last page) where it was necessary to put state symbols?


The Born-Haber cycle


Posted from TSR Mobile
Reply 3670
Avatar for Jm098
Jm098
2
Original post by GetOverHere
So did I, it's fine because you'd be reacting an acid and an alkali, getting a salt (Cu(HCOO)2) and water.


Posted from TSR Mobile


reckon they'd allow copper sulphate reacting to form sulphuric acid and the salt?
Original post by Jm098
reckon they'd allow copper sulphate reacting to form sulphuric acid and the salt?


TBH I think because they said any copper compound, as long as copper sulfate and methanoic acid react to form that, it should be OK. The only thing is that you've made another acid in the process so I'm not sure if that might be marked wrong due to the fact that making an acid would influence the titration.


Posted from TSR Mobile
For the entropy question, I think I used the lattice enthalpy as delta H. How many marks would this lose?
Reply 3673
Avatar for Jm098
Jm098
2
Original post by GetOverHere
TBH I think because they said any copper compound, as long as copper sulfate and methanoic acid react to form that, it should be OK. The only thing is that you've made another acid in the process so I'm not sure if that might be marked wrong due to the fact that making an acid would influence the titration.


Posted from TSR Mobile

ok thank you :smile:
i find out that i mess up the concepts of cis and trans......
Original post by GetOverHere
The Born-Haber cycle


Posted from TSR Mobile


Awesome, thanks
Reply 3676
Avatar for Cal 1
Cal 1
2
Original post by GetOverHere
So did I, it's fine because you'd be reacting an acid and an alkali, getting a salt (Cu(HCOO)2) and water.


Posted from TSR Mobile


Unfortunately no. Correct me if I'm wrong, but the question wanted Cu2+ ions, and Cu(OH)2 is a solid in water(precipitate) so wouldn't work:/
That question on oxidising and reducing agent was 6 marks and I def got that reducing equation wrong because I said it would react with 3 - 6 redox systems instead of just one.
How many marks do people think thats worth?
Reply 3678
Avatar for Cal 1
Cal 1
2
Original post by Jm098
reckon they'd allow copper sulphate reacting to form sulphuric acid and the salt?


That's what I did. No reason why not I don't think!
Does anyone remember what happens with chemical shift when agno3 is added?

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you