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AQA CHEM5 A2 Chemistry - 19th June 2013

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I feel the same way, the only thing is that it's synoptic so in the exam they could ask you about anything from AS and also unit4 :frown:

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I did unit 5 in january (without doing unit 4, currently studying for it). This is the case for biology, but not for chemistry :biggrin:

Reply 421

amelia95

Anyone have any idea what the mock paper is gonna be? Hate this unit and worst EMPA ever!

Reply 422

username890104

Original post by Ren_9

I feel the same way, the only thing is that it's synoptic so in the exam they could ask you about anything from AS and also unit4 :frown:

Not quite:

The units CHEM4 and CHEM5 can be taken in either order. Therefore synoptic assessment in these modules will assume only a knowledge and understanding of the material in the AS modules.

There will be no material from CHEM4 assessed in CHEM5 and no CHEM5 material assessed in CHEM4.

Reply 423

Ren_9

Original post by Tullia

Not quite:

:smile:

Okay, well thats good to know! :biggrin:

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Reply 424

AspiringDoctor

Sorry if it's been asked but is the [Co(NH3)6]3+ ion "darker brown" or "yellow"? The Summary Sheet says darker brown than [Co(H2O)6]2+ but the Nelson Thornes book quotes yellow.

This is the ion left after the ammonical oxidation of [Co(H2O)6]2+ to form [Co(NH3)6]2+ which has been oxidised.

Reply 425

laurawoods

Original post by AspiringDoctor

Hello, the 2+ complex (with NH3 ligands) is meant to be straw coloured whereas the 3+ complex (with NH3 ligands) is meant to be dark brown! And also remember that the reason why you make into [Co(NH3)6]2+ rather than the hexaaqua complex is because the former is easier to oxidise than the latter! And oxidation is done by oxygen in the air or if you want it to be quicker you use H202 with dilute NaOH. Does that help? :smile:

(P.S. The 2+ complex with water ligands is that classic PINK colour! When you add a lit bit of ammonia, a ppt is formed- colour of ppt is blue! Cu (OH)2. But when excess ammonia is used, the straw coloured solution is produced because a ligand substitution reaction has occurred. This then becomes dark brown because going from Co2+ to Co3+).

(edited 10 years ago)

Reply 426

JenniS

Original post by AspiringDoctor

Original post by laurawoods

Hello, the 2+ is meant to be straw coloured whereas the 3+ is meant to be brown!

definately brown for 3+, we just did a paper and you only got the mark for (dark) brown

Reply 427

laurawoods

Original post by JenniS

definately brown for 3+, we just did a paper and you only got the mark for (dark) brown

Hello, if you read carefully that is what I have said..3+ complex with NH3 ligands is brown!

(edited 10 years ago)

Reply 428

Xiomara

Original post by erniiee

Strangely for me, Transition metals are my favourite topic. I'm scared to look at redox equilibria and the rest of electrochemistry though :lol:

Really? I'm struggling with all the memorisation! And I was afraid of redox equilibria until I actually sat down and worked through the resources on a-levelchemistry, now I love it haha!

Reply 429

laurawoods

Original post by laurawoods

Hello, if you read carefully that is what I have said..3+ complex with NH3 ligands is brown!

Along with negging, pls can people who neg also provide the reason for negging me in this way? I was only trying to help out people who had some doubts .... pls don't be so discouraging. If you had any problems with my answer, pls quote and tell 'face to face' Just putting a neg and then running away is childish and spiteful behaviour! :smile:

Reply 430

erniiee

Original post by frogs r everywhere

I found Unit 5 so so much easier than unit 4. I don't know why.

Somehow, (I think its the fact I'm doing them concurrently) I find it makes more sense? I even enjoyed learning the colours of the transition metals. And the calculations are always doable?

Whereas I was so bad at AS Chemistry as I couldn't cope with mechanisms (bad teaching leads to loathing haha) - I scraped an A after a remark. So CHEM4, involving remembering AS stuff hasn't been too enjoyable, but now that I've actually learnt the stuff it isn't so bad!

Overall, I just like Chemistry more this year!

Reply 431

erniiee

Original post by Xiomara

Really? I'm struggling with all the memorisation! And I was afraid of redox equilibria until I actually sat down and worked through the resources on a-levelchemistry, now I love it haha!

We've spent so long on this topic and done so many questions for practice so I've remembered most of it! Ah okay so you'd recommend a-levelchemistry for redox equilibria?

Reply 432

JenniS

Original post by laurawoods

Hello, if you read carefully that is what I have said..3+ complex with NH3 ligands is brown!

I was agreeing with you! and btw I didn't neg you... :smile:

Reply 433

AspiringDoctor

Original post by laurawoods

Original post by JenniS

Cheers guys, +rep x

Reply 434

AmyLH

Finally getting somewhere now, just working through the old spec exam questions and will start on past papers in a few weeks. Got the first part of my mock a week Monday :frown:

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Reply 435

Sherlockedd

Original post by AmyLH

Finally getting somewhere now, just working through the old spec exam questions and will start on past papers in a few weeks. Got the first part of my mock a week Monday :frown:

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That's good in a way though, get some good practice! :smile:

Reply 436

erniiee

Original post by Xiomara

Really? I'm struggling with all the memorisation! And I was afraid of redox equilibria until I actually sat down and worked through the resources on a-levelchemistry, now I love it haha!

Dunno who negged you so I've repped you to even it out :smile:

Reply 437

Xiomara

Original post by erniiee

We've spent so long on this topic and done so many questions for practice so I've remembered most of it! Ah okay so you'd recommend a-levelchemistry for redox equilibria?

I'd recommend that site for pretty much everything! It's useful to have pretty much the entire spec in one place. Wish I hadn't invested in the Nelson Thornes A2 book now, as it's just not helpful in comparison to these free resources.

Original post by erniiee

Dunno who negged you so I've repped you to even it out :smile:

Aww, that's very kind! Thank you :smile:

When I get some rep power back I'll return the favour haha.

Reply 438

erniiee

Original post by Xiomara

When I get some rep power back I'll return the favour haha.

No problem :smile:

That is so true, its very kind of people to put these up for free! I'll check it out for redox then, I was using it for a lot of CHEM4 stuff. Yea, the Nelson thornes textbook isn't great, I think it complicates a lot of things unnecessarily

Reply 439

Xiomara

Original post by erniiee

No problem :smile:

Repped

It's amazing, covers AS and A2 for AQA and OCR, as well as some helpful ISA tips. For each section, it has understanding notes, a test, and then a pack of past paper questions and answers to test yourself. As you said, the NT book can be quite complicated and far too wordy when it doesn't need to be (more so for Physics, but hey) and it doesn't actually seem to cover everything on the specification. Some of the examples aren't great either and it's riddled with typos. The exam style questions are good, but if your college doesn't have Kerboodle it's a mission to get the answers!