Edexcel Chemistry A2 Unit 5 ~ Wednesday 19th June 2013 (Now Closed)

Not long now, how is everyone coping? I'm just about seeing the light at the end of the tunnel.

Reply 1102

Original post by HarryMWilliams

Not long now, how is everyone coping? I'm just about seeing the light at the end of the tunnel.

hopefully i'll be seeing that soon too :smile:

I really want an A* but I can't seem to even get an A grade in unit 5. It's quite off putting - I think i'm trying hard, i guess i just need to change my strategy. Have you started papers yet? :smile:

Reply 1103

Original post by jojo1995

hopefully i'll be seeing that soon too :smile:

I really want an A* but I can't seem to even get an A grade in unit 5. It's quite off putting - I think i'm trying hard, i guess i just need to change my strategy. Have you started papers yet? :smile:

Yah - I've done one or two, I'm focussing on the organic stuff at the moment. I quite like Unit 5 over the others, it's not 'easy' per se, but just nice. :biggrin:

Reply 1104

Original post by HarryMWilliams

Yah - I've done one or two, I'm focussing on the organic stuff at the moment. I quite like Unit 5 over the others, it's not 'easy' per se, but just nice. :biggrin:

yeah... you need to know the organic inside out - the jan grade boundaires are so high... for the one i just did, it was 80 FOR AN A* ??? WHY lol - I prefer unit 4 by 100% :tongue:

Reply 1105

Hi, does anyone know how to calculate the percentage error of a beaker, pipette, thermometer and anything else please ? :smile:

thank you in advance

Reply 1106

Ryejd

A hydrated transition metal ion is colourless. Which of the following could be the
electronic configuration of this ion?
A [Ar] 3d54s2
B [Ar] 3d8
C [Ar] 3d104s2
D [Ar] 3d10

why D and not C?

Reply 1107

Original post by jojo1995

yeah... you need to know the organic inside out - the jan grade boundaires are so high... for the one i just did, it was 80 FOR AN A* ??? WHY lol - I prefer unit 4 by 100% :tongue:

I quite like Unit 4 too actually - A2 is far much more interesting and enjoyable than AS.

Reply 1108

Original post by Ryejd

A hydrated transition metal ion is colourless. Which of the following could be the
electronic configuration of this ion?
A [Ar] 3d54s2
B [Ar] 3d8
C [Ar] 3d104s2
D [Ar] 3d10

why D and not C?

ion means it has lost electrons, and transition metals have thier outer electrons in 3d and 4s sub shells. so in order for it to be an ion it must have lost some electrons. electrons are lost from the 4s first :smile:

hopefully i've answered your question, i am quite bad at explaining.

Reply 1109

shumen9523

6

Original post by Ryejd

A hydrated transition metal ion is colourless. Which of the following could be the
electronic configuration of this ion?
A [Ar] 3d54s2
B [Ar] 3d8
C [Ar] 3d104s2
D [Ar] 3d10

why D and not C?

Hey,

C displays the electron configuration of an atom of zinc as the s-subshell is full.
D on the other hand does not have any electrons in the s-subshell which indicates that 2 electrons had been lost. This shows that it is the transition metal ion.

(edited 10 years ago)

Reply 1110

Tackla

14

Guys how are unit 5 papers? I done most of my revision,but haven't done a single paper yet. It looks scary lol :no:

Posted from TSR Mobile

Reply 1111

Original post by Tackla

Guys how are unit 5 papers? I done most of my revision,but haven't done a single paper yet. It looks scary lol :no:

Posted from TSR Mobile

The January 2013 (I think) paper with the copper question... good luck! :biggrin:

Otherwise, they aren't too bad. Some of the organic questions are just repeated (effectively) in each paper so I would suggest you learn those verbatim.

Reply 1112

blossomx

20

Hey, could someone please just check my thought process is correct.

When a redox reaction produces a solid, the equilibrium moves to the right (so the constant increases) so the value for the cell's emf will increase? Which explains why, despite a negative Ecell, it could still occur?

Reply 1113

ayeswary

Original post by jojo1995

Hi, does anyone know how to calculate the percentage error of a beaker, pipette, thermometer and anything else please ? :smile:

thank you in advance

Hi to calculate the percentage error for the apparatus
%error
= the uncertainty in the equipment divided by the reading an then you times 100%

This kind of questions they will sometimes give you the titre reading so u use that and divide with the reading and times with 100%.
Hope you understand what I meant. If you don't then let me know yeah.
Cheers. :smile:

😊
If they don't give you the titre reading then u have to calculate it by yourself where you 2 times with the uncertainty of the equipment and then divide with the reading and times with 100%.

Posted from TSR Mobile

Reply 1114

Original post by ayeswary

Hi to calculate the percentage error for the apparatus
%error
= the uncertainty in the equipment divided by the reading an then you times 100%

This kind of questions they will sometimes give you the titre reading so u use that and divide with the reading and times with 100%.
Hope you understand what I meant. If you don't then let me know yeah.
Cheers. :smile:

😊
If they don't give you the titre reading then u have to calculate it by yourself where you 2 times with the uncertainty of the equipment and then divide with the reading and times with 100%.

Posted from TSR Mobile

Thank you so much :smile:

do you know how I'd calculate the uncertainty ?

Reply 1115

Gnome :)

Original post by jojo1995

Thank you so much :smile:

do you know how I'd calculate the uncertainty ?

So if you have a burette that measures to 0.1cm3, you uncertainty is +/- 0.05, so 0.05*2=0.1 :smile:

Reply 1116

JRP95