[CelineG]

Hi can anyone let me know what electrochemical cells we need to know off by heart in the redox equilibira section pleasee?

[wibletg]

(Original post by CelineG)
Hi can anyone let me know what electrochemical cells we need to know off by heart in the redox equilibira section pleasee?

From the spec:

• appreciate that electrochemical cells can be used as a commercial source of electrical energy
• appreciate that cells can be non-rechargeable (irreversible), rechargeable and fuel cells
• be able to use given electrode data to deduce the reactions occurring in non-rechargeable and rechargeable cells and to deduce the e.m.f. of a cell
• understand the electrode reactions of a hydrogen-oxygen fuel cell and appreciate that a fuel cell does not need to be electrically recharged
• appreciate the benefits and risks to society associated with the use of these cells

So you only need to remember the reactions for the hydrogen fuel cell

[NoFunnyBusiness]

(Original post by Sheo)
Do we need to know the equations for when the aqua ions react w/ OH-, NH3 and CO3 2-? Thanks

CHEM5!!!!

[Crystal_Heart]

Hey,
Just wondering if anyone knows what colour CuCO3 is?

Cuz i've been taught that it's green-blue ppt, but i did a paper (jun 10) and the mark scheme says it's green ppt or blue-green ppt.

My teacher's insisting it's green-blue ppt (somehow I doubt this), could anyone clear this up for me? Thanksss x

[Glacier]

(Original post by Crystal_Heart)
Hey,
Just wondering if anyone knows what colour CuCO3 is?

Cuz i've been taught that it's green-blue ppt, but i did a paper (jun 10) and the mark scheme says it's green ppt or blue-green ppt.

My teacher's insisting it's green-blue ppt (somehow I doubt this), could anyone clear this up for me? Thanksss x

Page 242 of the Nelson Thornes textbook says blue-green, so I would write that.

[wibletg]

(Original post by Crystal_Heart)
Hey,
Just wondering if anyone knows what colour CuCO3 is?

Cuz i've been taught that it's green-blue ppt, but i did a paper (jun 10) and the mark scheme says it's green ppt or blue-green ppt.

My teacher's insisting it's green-blue ppt (somehow I doubt this), could anyone clear this up for me? Thanksss x

Blue green ppt. (not that I'd say there's much difference between the two!)

Have you got a copy of the AQA endorsed textbook? The colours are in there

[Crystal_Heart]

@Glacier and @wibletg

Thanks for your help! I have got the Nelson Thornes book, but I keep being told different colours by school! :/ Veryyy confusing! I think I'll stick with what the textbook says.

[timoaf]

Hey does anyone know the colour of the hexaaquairon(III) ion? the Fe(H20)6 3+ one? My textbook (Saunders) says it's pale violet but my teacher says orange ?!

[NoFunnyBusiness]

Does Anyone have a list of the chemical equations we are meant to know for this exam?

[wibletg]

(Original post by timoaf)
Hey does anyone know the colour of the hexaaquairon(III) ion? the Fe(H20)6 3+ one? My textbook (Saunders) says it's pale violet but my teacher says orange ?!

They tend to accept brown, yellow or purple (might be violet, not sure without checking).

Personally I use brown solution because it turns into a brown gelatinous ppt so it makes it easier to remember


EDIT:

Can anyone help with this question:
http://www.thestudentroom.co.uk/show....php?t=2009577

[MuffinMonster]

(Original post by wibletg)
They tend to accept brown, yellow or purple (might be violet, not sure without checking).

Personally I use brown solution because it turns into a brown gelatinous ppt so it makes it easier to remember


EDIT:

Can anyone help with this question:
http://www.thestudentroom.co.uk/show....php?t=2009577

I answered it on the thread

[shuaib786]

(Original post by Doctor.)
How many of you guys are resitting CHEM4?

PS I did CHEM5 in January and it was a rush to finish the questions, so be preped for rushing the exam papers! Even people with extra time were still pushing their luck .

I am see you'll all be fine, there's a AQA CHEM4 thread btw, if you need any questions answered I can try my best to help. Just PM me or hit me up on the CHEM4 thread. I am like a ninja on there

Happy learning

Is there a chem 4 thread???

[Erotas]

(Original post by wibletg)
From the spec:

• appreciate that electrochemical cells can be used as a commercial source of electrical energy
• appreciate that cells can be non-rechargeable (irreversible), rechargeable and fuel cells
• be able to use given electrode data to deduce the reactions occurring in non-rechargeable and rechargeable cells and to deduce the e.m.f. of a cell
• understand the electrode reactions of a hydrogen-oxygen fuel cell and appreciate that a fuel cell does not need to be electrically recharged
• appreciate the benefits and risks to society associated with the use of these cells

So you only need to remember the reactions for the hydrogen fuel cell

Hey, do you know if this means that we have to learn the specific equations on pages 208-211 in the NT book?

[MuffinMonster]

(Original post by Erotas)
Hey, do you know if this means that we have to learn the specific equations on pages 208-211 in the NT book?

The blue boxes say detailed knowledge of the cells are not required. But the hydrogen fuel cells bit are important.

[undertaker1]

anyone have the jan 12 paper???

[tobnot]

(Original post by undertaker1)
anyone have the jan 12 paper???

Yeah here's the paper and mark scheme!

[shuaib786]

(Original post by tobnot)
Yeah here's the paper and mark scheme!

Thanks for uploads. I have just done that paper and it was horrible.

[wibletg]

I'm running out of questions to do

I only have Jan 12 as a paper left to do now.

I've even done some CHM5 papers but they're really repetitive, as well as the booklets of papers from a-levelchemistry.co.uk

What else can I do? Do any exam boards offer similar question papers to CHEM5??

[shuaib786]

(Original post by wibletg)
I'm running out of questions to do

I only have Jan 12 as a paper left to do now.

I've even done some CHM5 papers but they're really repetitive, as well as the booklets of papers from a-levelchemistry.co.uk

What else can I do? Do any exam boards offer similar question papers to CHEM5??

You could revise ur notes. I mean I kinda notice now they kinda like asking new questions. Chem 5 is such a bitch though. Can someone give me help on how to do the conventional representation of cells.

[wibletg]

(Original post by shuaib786)
You could revise ur notes. I mean I kinda notice now they kinda like asking new questions. Chem 5 is such a bitch though. Can someone give me help on how to do the conventional representation of cells.

I'm reading through the textbook but there's only so much of that you can do

It's likely we'll get a funny paper though.

I'll leave the conventional cell representation to someone else as I've only just started to understand it myself