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

Poll: How pumped up are you for this exam?-(warning)-(bad jokes arene this poll!)
"Titanium-I'm not going to corrode (even at high temperatures)" (A*) (22)
16.67%
"Benzene's my middle name, give me the paper in a week and I'll ace it!" (A) (27)
20.45%
"Yeah, I'm fairly electrophillic (positively charged) about the exam" (B) (27)
20.45%
"I'm in the middle of the salt bridge, but I will pass-eventually" (C) (21)
15.91%
"I'm feeling rather electroNegative about this exam" (D) (18)
13.64%
"Benzene, what's that?" (E) (6)
4.55%
"Chemistry, what's that?" (F) (11)
8.33%
This discussion is closed.
posthumus
Badges: 20
Rep:
?
#601
Report 6 years ago
#601
Hey guys

There are so many damn formulas for the complex ions ! :/

please don't tell me I need to remember all these ?

For example hydrated Copper(II)chloride can be reacted with 4 moles of NH3
or 3 moles of 1,2-diaminoethane,
or 1 mole of ethanediaminetetraacetate
and so on...

to form all sorts of funky stuff ! ... its all just too much to remember !

I'm referring to the george facer book I know it can be unnecessary, but I just want to make sure !
0
jojo1995
Badges: 2
Rep:
?
#602
Report 6 years ago
#602
does anyone know what the max temperature for the reaction of benzene to form nitrobenzene is in markshemes ? i say 60 degrees is the temp is should be done at and it has to be above 55 but below 65 is that fine ?

different books say differnt things
thank you
0
posthumus
Badges: 20
Rep:
?
#603
Report 6 years ago
#603
(Original post by jojo1995)
does anyone know what the max temperature for the reaction of benzene to form nitrobenzene is in markshemes ? i say 60 degrees is the temp is should be done at and it has to be above 55 but below 65 is that fine ?

different books say differnt things
thank you
60 should be fine in the exam
0
yahyazhar
Badges: 4
Rep:
?
#604
Report 6 years ago
#604
hey guys, I just wanted to ask if anyone has this document that has all the chemical tests compiled together? I used to have it but I can't find it anymore, if anyone has it, can you please share a link?

(this is kindof a paper 6 request, but this is the only -active- thread i found)

thanks!
0
jojo1995
Badges: 2
Rep:
?
#605
Report 6 years ago
#605
(Original post by posthumus)
60 should be fine in the exam
Thanks a lot
0
MustaphaMond
Badges: 11
Rep:
?
#606
Report 6 years ago
#606
Do we need to know all the specific reactions of copper (I) and copper (II)???
There's too much to remember and it's all abstract and hard to learn.
0
posthumus
Badges: 20
Rep:
?
#607
Report 6 years ago
#607
(Original post by lordmackery)
Do we need to know all the specific reactions of copper (I) and copper (II)???
There's too much to remember and it's all abstract and hard to learn.
(Original post by posthumus)
Hey guys

There are so many damn formulas for the complex ions ! :/

please don't tell me I need to remember all these ?

For example hydrated Copper(II)chloride can be reacted with 4 moles of NH3
or 3 moles of 1,2-diaminoethane,
or 1 mole of ethanediaminetetraacetate
and so on...

to form all sorts of funky stuff ! ... its all just too much to remember !

I'm referring to the george facer book I know it can be unnecessary, but I just want to make sure !
This.

I had the same question Someone help us !!!!
0
jojo1995
Badges: 2
Rep:
?
#608
Report 6 years ago
#608
(Original post by posthumus)
This.

I had the same question Someone help us !!!!
You Defo need to know ammonia. We have learnt different ones such as EDTA, at my school and my teacher says we do need to know them ... I think they are more likely to be on mc though
0
LeaX
Badges: 20
Rep:
?
#609
Report 6 years ago
#609
This is going to sound like such a stupid question but it's something that I always mess up on in exam questions.

For redox, when working out the mole ratios do you just do the ionic equation or the whole compound? I've learnt the manganate one but I don't understand why it's the way it is. Why do you put MnO4- in it? Why not KMnO4? You only put the ion (Mn2+) for the product so why can't you put Mn5+ + 3e -> Mn2+ ??

Thank you.
0
posthumus
Badges: 20
Rep:
?
#610
Report 6 years ago
#610
(Original post by jojo1995)
You Defo need to know ammonia. We have learnt different ones such as EDTA, at my school and my teacher says we do need to know them ... I think they are more likely to be on mc though
Thanks !

Okay well I guess its not too much Just copper & chromium reactions to remember ? But I don't need to know the full name of EDTA or the structure of it right ?
0
posthumus
Badges: 20
Rep:
?
#611
Report 6 years ago
#611
(Original post by LeaX)
This is going to sound like such a stupid question but it's something that I always mess up on in exam questions.

For redox, when working out the mole ratios do you just do the ionic equation or the whole compound? I've learnt the manganate one but I don't understand why it's the way it is. Why do you put MnO4- in it? Why not KMnO4? You only put the ion (Mn2+) for the product so why can't you put Mn5+ + 3e -> Mn2+ ??

Thank you.
That's actually a good question Usually the MnO4- is together as one ionic group - but I mean they usually want you to figure out that manganate is in the +5 oxidation state... you would only work that out if you had oxygen? (because that is what has oxidised the manganate ions in a way to make them in the +5 state, I think )

But in all honesty, I'm not sure why exactly
0
jojo1995
Badges: 2
Rep:
?
#612
Report 6 years ago
#612
(Original post by posthumus)
Thanks !

Okay well I guess its not too much Just copper & chromium reactions to remember ? But I don't need to know the full name of EDTA or the structure of it right ?
Don't we need to know zinc as well? Fe also ? Who saîd we only need to know cr and cu? I thought we needed to know most if the top row if transition metals - fe mn cu cr zn and I cantvremember the others off head
No you don't need to know the structure or real name of EDTA - just that it's charge is 4- and it has the ability to for 6 ligandish bonds
0
posthumus
Badges: 20
Rep:
?
#613
Report 6 years ago
#613
(Original post by jojo1995)
Don't we need to know zinc as well? Fe also ? Who saîd we only need to know cr and cu? I thought we needed to know most if the top row if transition metals - fe mn cu cr zn and I cantvremember the others off head
No you don't need to know the structure or real name of EDTA - just that it's charge is 4- and it has the ability to for 6 ligandish bonds
Ah cr*p, your right

Okay that's a relief... and also some cations can have a certain number of ligands due to sizes of the atoms we don't need to remember how many ligands a cation can have?
0
F1's Finest
Badges: 21
Rep:
?
#614
Report 6 years ago
#614
(Original post by LeaX)
This is going to sound like such a stupid question but it's something that I always mess up on in exam questions.

For redox, when working out the mole ratios do you just do the ionic equation or the whole compound? I've learnt the manganate one but I don't understand why it's the way it is. Why do you put MnO4- in it? Why not KMnO4? You only put the ion (Mn2+) for the product so why can't you put Mn5+ + 3e -> Mn2+ ??

Thank you.
It's alot easier to see charges, because your given it, as an ionic equation!

I'm sure you know what I meant by ionic equations!

It's easier to see the charge on the atoms and hence allows you to see which got oxidised and reduced, more easily. :yy:
0
LeaX
Badges: 20
Rep:
?
#615
Report 6 years ago
#615
(Original post by posthumus)
Ah cr*p, your right

Okay that's a relief... and also some cations can have a certain number of ligands due to sizes of the atoms we don't need to remember how many ligands a cation can have?

(Original post by James A)
It's alot easier to see charges, because your given it, as an ionic equation!

I'm sure you know what I meant by ionic equations!

It's easier to see the charge on the atoms and hence allows you to see which got oxidised and reduced, more easily. :yy:
Thank you both.
0
jojo1995
Badges: 2
Rep:
?
#616
Report 6 years ago
#616
(Original post by posthumus)
Ah cr*p, your right

Okay that's a relief... and also some cations can have a certain number of ligands due to sizes of the atoms we don't need to remember how many ligands a cation can have?


I think we do I keep breaking you bad news today

For eg cu+ forms cucl2
Whilst cu2+ forms cucl4

The reactions are in the blue edexcel book so I think you gosta know them.

Most of the transition metals fo compumounds w/ 6 h2os

Maximum nh3 is usually 4 so [cu(nh3)4(h20)2]

You don't have to include the h20 here if you don't want to fml I need to revise this stuff
0
posthumus
Badges: 20
Rep:
?
#617
Report 6 years ago
#617
(Original post by jojo1995)

I think we do I keep breaking you bad news today

For eg cu+ forms cucl2
Whilst cu2+ forms cucl4

The reactions are in the blue edexcel book so I think you gosta know them.

Most of the transition metals fo compumounds w/ 6 h2os

Maximum nh3 is usually 4 so [cu(nh3)4(h20)2]

You don't have to include the h20 here if you don't want to fml I need to revise this stuff
Aaaah damn More stuff to memorise !!

I guess I'll save memorizing for near exam time... I'm just going to try and make sure I understand every fundamental concept in all Chemistry units

Thanks for your help once again !
1
MustaphaMond
Badges: 11
Rep:
?
#618
Report 6 years ago
#618
Can somebody answer my question about copper please??
0
MustaphaMond
Badges: 11
Rep:
?
#619
Report 6 years ago
#619
And do we need to know how to calculate Kstab? It's not in my textbook but it's in my revision guide?? Very confused.
0
posthumus
Badges: 20
Rep:
?
#620
Report 6 years ago
#620
(Original post by lordmackery)
And do we need to know how to calculate Kstab? It's not in my textbook but it's in my revision guide?? Very confused.
jojo1995 responded to your copper question (as well as my question) and yes you do have to remember all those reactions unfortunately. This unit has less new organic to remember - but there's a lot of redox/ complex reactions to remember also

Erm I'm not too sure about that Kstab... but its only a very short part of the george facer book there's nothing really to remember Ka (from unit 4)... it's the same thing pretty much.
0
X
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

University open days

  • University of Surrey
    Postgraduate Open Afternoon Postgraduate
    Wed, 23 Oct '19
  • University of Bristol
    Undergraduate Open Afternoon Undergraduate
    Wed, 23 Oct '19
  • University of Exeter
    Undergraduate Open Day - Penryn Campus Undergraduate
    Wed, 23 Oct '19

Would you turn to a teacher if you were being bullied?

Yes (53)
25.6%
No (154)
74.4%

Watched Threads

View All