You are Here: Home

ocr a f325 revision thread watch

1. so I still don't get Q63) jan 2013??? someone help pls....
2. (Original post by AFC_123456789)
Hey thanks for the reply. So it has cis-trans but NOT optical isomerism right?

And i mean does chloride donate lp to platinum. The 2N atoms obviously do but do the 2 chloride as well? Thanks man
Oh yeah, sorry, I meant 'no, it *doesn't have optical isomerism'.

Oh right, yeah the chloride ions also donate one lone pair to the platinum each (all ligands must donate at least one lone pair to the central metal ion to be able to form the coordiante/dative covalent bond).
3. (Original post by Nuna)
so I still don't get Q63) jan 2013??? someone help pls....
which question?
Oh yeah, sorry, I meant 'no, it *doesn't have optical isomerism'.

Oh right, yeah the chloride ions also donate one lone pair to the platinum each (all ligands must donate at least one lone pair to the central metal ion to be able to form the coordiante/dative covalent bond).
No worries. So are there a total of 4 ligands in cis platin?
5. (Original post by Nuna)
so I still don't get Q63) jan 2013??? someone help pls....
I assume you mean question 6e) Basically you write out equations for both cr3+ and x, the x equation is x->x2+ +2e-

You combine the 2 equations and you get the mole ration. The you work out the moles of chronium by doing 1.456/52 to get 0.028. As the mole ratio is 3:2 the moles of X are 0.042.

You can then work out the mr by doing n=m/mr and you get the answer to be Mg
6. (Original post by AFC_123456789)
No worries. So are there a total of 4 ligands in cis platin?
Yep, two NH3 and two Cl-.
7. (Original post by eggfriedrice)
In Jan 2013 q8) ci. There is no clear color change at the end point but why in the mark scheme talk about the colours at the START of the reaction?

MnO4- is purple and Vn+ is violet, however surely only the ending point colours would matter which are yellow and pale pink.
Because they#'e both purple it would be difficult to tell when the end point has been reached in the first place.

You're adding a purple solution to a purple solution and looking for an end-point which is a mix between pink and yellow. The colours are all too similar to make a clear distinction of an end point.

Hope that makes sense!
Yep, two NH3 and two Cl-.
You're a top guy! Good luck pal
9. (Original post by AFC_123456789)
You're a top guy! Good luck pal
Thanks, you too!
10. can someone tell me how to do June 12 q3 cii?
11. (Original post by bill7202)
can someone tell me how to do June 12 q3 cii?
Mg2+ has a smaller ionic radius and greater charge than Na+ (Remember when it comes to differences in charge you have to mention BOTH ionic radius and charge) Mg2+ has a greater charge density than Na+, Mg2+ as a greater attraction for water molecules than Na+.

Its like the same thing I write for all of these exams except the ions are different.
12. (Original post by beccac94)
Mg2+ has a smaller ionic radius and greater charge than Na+ (Remember when it comes to differences in charge you have to mention BOTH ionic radius and charge) Mg2+ has a greater charge density than Na+, Mg2+ as a greater attraction for water molecules than Na+.

Its like the same thing I write for all of these exams except the ions are different.
i think you're looking at a different question, june 12 q3 cii is a buffer solution question
13. (Original post by bill7202)
i think you're looking at a different question, june 12 q3 cii is a buffer solution question
Ohhhhh I completely misread that question I thought it was Jan 13, I was still on an earlier comment

Don't really feel like I needed to be negged for that though :/
14. I'm off now good luck everyone!!
15. Did this paper turn out to be a lot nicer than the Jan 13 paper?
16. (Original post by Mastermind2)
Did this paper turn out to be a lot nicer than the Jan 13 paper?
Much easier.

Posted from TSR Mobile

EDIT: Woah whats with the hate? Nobody can deny that it was so much easier than January's, that paper was horrible!
17. How does everybody think it went? I thought it was challenging but I think I've done well!
18. (Original post by jess_m94)
How does everybody think it went? I thought it was challenging but I think I've done well!
I thought it went really well, what did you (or anyone) get for the last part of the last question?
19. (Original post by jess_m94)
How does everybody think it went? I thought it was challenging but I think I've done well!
Some questions were easy but the last question ...
20. I thought it went well ish, but I still found it a hard paper, if that makes sense. I'm not exactly jump up and down happy about the paper but I got through it. Easier than Jan 2013, harder than June 2012, imo.

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: June 8, 2014
Today on TSR

The most controversial member on TSR?

Who do you think it is...

Uni strikes! How do they affect you?

Discussions on TSR

• Latest
Poll
Useful resources

Can you help? Study Help unanswered threadsStudy help rules and posting guidelines

Groups associated with this forum:

View associated groups
Discussions on TSR

• Latest

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE