Chemistry Paper 4-theory- doubts =D

[Khalifa]

Not always the case, its just a possibility.

Dude I would appreciate it if you can give me a clearer answer

 

[nishan2052]

do u mean the splitting of the degenerate d orbitals to non-degenerate d orbitals during the formation of complex ions ?

yeah ...please explain the splitting part and how it is formed.

 

[knowitall10]

yeah ...please explain the splitting part and how it is formed.

iKhaled are u replying or should i?

 

[iKhaled]

iKhaled are u replying or should i?

how about both of us?

 

[nishan2052]

iKhaled are u replying or should i?

u must reply.

 

[nishan2052]

how about both of us?

 

[Jinkglex]

Dude I would appreciate it if you can give me a clearer answer

Well its basically that sometimes second electron affinity can be positive, sometime it can be negative, it just depends on the compound AFAIR

 

[iKhaled]

yeah ...please explain the splitting part and how it is formed.

alright man..the d orbitals contain electrons so when a ligand comes close to the central ion of the transition metal the lone pairs on the ligand repels the electrons in the d orbitals and this causes the d orbitals to split into 5 orbitals..3 at low level and 2 at high level..the energy gap between the 2 levels depends on the type of ligand which is forming dative bonds with the transition metal, some ligand form big energy gaps and some form small energy gap. also the charge on the transition metal ion is responsible for the energy gap size. now this gap is why we have all our transition metals colored. when light hits the metal the electron from the low energy level absorbs energy from light and is excited to to the higher energy level orbital, from here we get our colour of the transition metal.

 

[Jinkglex]

alright man..the d orbitals contain electrons so when a ligand comes close to the central ion of the transition metal the lone pairs on the ligand repels the electrons in the d orbitals and this causes the d orbitals to split into 5 orbitals..3 at low level and 2 at high level..the energy gap between the 2 levels depends on the type of ligand which is forming dative bonds with the transition metal, some ligand form big energy gaps and some form small energy gap. also the charge on the transition metal ion is responsible for the energy gap size. now this gap is why we have all our transition metals colored. when light hits the metal the electron from the low energy level absorbs energy from light and is excited to to the higher energy level orbital, from here we get our colour of the transition metal.

I would like to add a little point to that:

the reason they split the D-orbitals in such a way is that Dx Dy Dz are not on the line whereas Dx2y2 and Dz2 are. On the line meaning they are directly in the way of the ligand and transition elements bond, whereas the others are not.

 

[railey]

S/a,
Hope all good
Can someone please help me understand the degenerate and non-degenerate part of the transition metals.

 

[iKhaled]

I would like to add a little point to that:

the reason they split the D-orbitals in such a way is that Dx Dy Dz are not on the line whereas Dx2y2 and Dz2 are. On the line meaning they are directly in the way of the ligand and transition elements bond, whereas the others are not.

another point also the bigger the gap the more energy it will absorb and this will result in a deeper colour of complex ion.. correct me Jinkglex if i am wrong

 

[iKhaled]

S/a,
Hope all good
Can someone please help me understand the degenerate and non-degenerate part of the transition metals.

omg!! it has just been explained a minute ago read the post above urs!

 

[Soldier313]

Aoa wr wb

Can someone please explain:

qn 2 cii and 2 ciii of this paper? and for part 2 c iii, if thee's more than one way of doing it, can you please share all the possible methods?
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w06_qp_4.pdf
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w06_ms_4.pdf

qn 4 bii
qn 6 b ii) why don't we have to use concentrated solutions and a high temperature?
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w07_qp_4.pdf
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w07_ms_4.pdf

qn 1 aii) why is the ms quoting the value of the electrode potential to be negative?
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_s08_qp_4.pdf
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_s08_ms_4.pdf

Thank you so much!

 

[kelly sheers]

Well its basically that sometimes second electron affinity can be positive, sometime it can be negative, it just depends on the compound AFAIR

Dude I would appreciate it if you can give me a clearer answer

2nd electron affinity is usually positive i believe

 

[iKhaled]

Aoa wr wb

Can someone please explain:

qn 2 cii and 2 ciii of this paper? and for part 2 c iii, if thee's more than one way of doing it, can you please share all the possible methods?
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w06_qp_4.pdf
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w06_ms_4.pdf

qn 4 bii
qn 6 b ii) why don't we have to use concentrated solutions and a high temperature?
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w07_qp_4.pdf
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w07_ms_4.pdf

qn 1 aii) why is the ms quoting the value of the electrode potential to be negative?
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_s08_qp_4.pdf
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_s08_ms_4.pdf

Thank you so much!

btw the last question u have posted here is correct in the mark scheme Oo its positive in the mark scheme not negative

 

[nishan2052]

I would like to add a little point to that:

the reason they split the D-orbitals in such a way is that Dx Dy Dz are not on the line whereas Dx2y2 and Dz2 are. On the line meaning they are directly in the way of the ligand and transition elements bond, whereas the others are not.

please make it clear about the line.jinglex

 

[knowitall10]

Oh wow...i don't need to reply anymore now do i nishan2052
Actually, i have my stats exam tmw...and i should b studying....(Should be)

 

[knowitall10]

Sorry i couldn't be useful man...well! Welcome to knowitall10! The absolutely useless person at the forum

 

[kelly sheers]

Hi guys. Can someone please tell me why first electron affinity is exothermic while the second one is endothermic?

Electron affinity (first electron affinity) is when an electron has been added to an atom to form an ion with a single negative charge. It is exothermic because the electron is attracted by the nuclear charge of the atom and energy is given off. The second electron affinity means you have to add an electron to negative ion. They repel. You need to do work to overcome the repulsion. So put energy in ( endothermic reaction)

 

[nishan2052]

Sorry i couldn't be useful man...well! Welcome to knowitall10! The absolutely useless person at the forum

i m totally new to these discussion.so forgive me.