AQA - Unit 5 - Energetics, Redox and Inorganic Chemistry

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Reply 1140

Sparkly-Star

Yeah these new papers seem to have stuff that we haven't even learnt about!!

Reply 1141

Seher

Original post by Arab_Empress

Yes and Thank God for that, I will honesly sleep for as long as I can, and do nothing for a long time,,,literally :biggrin:

yeah I don't really know if tomorrow's gonna be the start of a well deserved break for me... or the first day of a long life of unemployement :tongue:

but either way.... gona try and enjoy my 7 weeks of being a future medic before results day destroys my delusions lol.

I might just stack up some food and coke cans and a load of dvds and just not get out of bed for like a week...

Reply 1142

Seher

Original post by Sparkly-Star

Yeah these new papers seem to have stuff that we haven't even learnt about!!

I thought that was just me, but yeahh they do :frown:

as if it's not bad enough learning it all and then they don't even stick to it :frown:

Reply 1143

loveheart120

quick Question
if the spec says
know that......
do u just have to be able to state it?

Reply 1144

Zabukar

Original post by Sparkly-Star

See above.

Just memorized it all using your method :P. Thanks. First thing Ill be doing when I sit that exam is writing the table out. Thats a good 17-20 Marks just on Metal aqua ions.

Reply 1145

A level Az

Original post by Seher

yeah I don't really know if tomorrow's gonna be the start of a well deserved break for me... or the first day of a long life of unemployement :tongue:

Way ahead of you on this :redface:

Exams haven't gone very well at all and I'm so annoyed at myself, so I can see myself being completely unproductive for the next few weeks until my inevitable breakdown on results day. Good luck for tommorow (or today rather) :biggrin:

Reply 1146

Zabukar

Original post by Seher

yeah I don't really know if tomorrow's gonna be the start of a well deserved break for me... or the first day of a long life of unemployement :tongue:

Seriously cant wait, :| To finish. Going to catch up on 2 years lack of sleep. This 2 years have made me :eek:

Reply 1147

starburst92

Original post by A level Az

Anyone have any idea how to do the last question (titration) on the january 2011 paper? I got up to working out 1.138x10^-3 but then I don't understand what they do after that? Why do you multiply it by 10 and where does 1000/5 come from?

http://www.a-levelchemistry.co.uk/AQA%20Chemistry/AQA%20A2%20Chemistry/Unit%205/Unit%205%20Past%20Papers%20and%20Revision%20Aids/AQA-CHEM5-W-QP-Jan11.pdf
http://www.a-levelchemistry.co.uk/AQA%20Chemistry/AQA%20A2%20Chemistry/Unit%205/Unit%205%20Past%20Papers%20and%20Revision%20Aids/AQA-CHEM5-W-MS-Jan11.pdf

Please help! :smile:

You multiply by 10 because you took a 25cm sample and you need to make it 250cm as its the orginal. The 1000/5 is because its conc= moles/volume. The volume you orginially started of with was 5cm^3.

Reply 1148

Seher

Original post by Zabukar

Seriously cant wait, :| To finish. Going to catch up on 2 years lack of sleep. This 2 years have made me :eek:

likewise. I just really hope it's all somehow paid off =/

Reply 1149

adam1232

hey could any one help me please im panicking lol
its about fuel cells on page 51 of the collins student revision book the electrode reactions say

o2 +2h20 +4e -------> 4oh emf =0.40

2h2 +4oh ------> 4h20 + 4e enf =0.83

total emf = 1.23

i thought it was e right - e left which would be 0.43???

Reply 1150

A level Az

Does Fe^3+ go to Fe^2+ in conc. HCL?

Reply 1151

A level Az

Original post by starburst92

You multiply by 10 because you took a 25cm sample and you need to make it 250cm as its the orginal. The 1000/5 is because its conc= moles/volume. The volume you orginially started of with was 5cm^3.

Shouldn't it be 250/5? Why is it 1000? :s-smilie:

Reply 1152

strawberry_cake

Whens everyone sleeping?? :biggrin:

Reply 1153

Seher

Original post by adam1232

I haven't looked at it yet but I think you reverse the bottom one bcos they should always be reductions... so that gives -0.83 then you can do less negative - more negative = 0.40 - -0.83 = 1.23

Reply 1154

Seher

Original post by strawberry_cake

Whens everyone sleeping?? :biggrin:

now... because new stuff just isn't going in any more lol gonna try and get up at 6ish and read through everything one more time. review all the colour and shiz. then prepare to get raped yet again by aqa. fun times.

Reply 1155

Sparkly-Star

Original post by A level Az

Shouldn't it be 250/5? Why is it 1000? :s-smilie:

That's what I thought but remember they're asking for concentration so just re-arrange the n=cv/100 equation. :grin:

Reply 1156

Seher

Original post by A level Az

Does Fe^3+ go to Fe^2+ in conc. HCL?

I don't think so... plus I don't think we need to know what the 3+ ions do with Cl-

Reply 1157

Seher

Off to bed now... good night everyone, best of luck for tomorrow :smile:

Reply 1158

Sparkly-Star

Original post by Zabukar

Just memorized it all using your method :P. Thanks. First thing Ill be doing when I sit that exam is writing the table out. Thats a good 17-20 Marks just on Metal aqua ions.

Yay, but don't waste your time writing out first. Just find the bit you need to do, and just do it for that particular metal. :yep:

Original post by Seher

I thought that was just me, but yeahh they do :frown:

as if it's not bad enough learning it all and then they don't even stick to it :frown:

That's what I thought! And I need a high grade in this. It seems as though this unit is the worst in terms of resources/what to learn. To make it worse the markscheme are ever so specific this time round.