ALL CIE CHEMISTRY DOUBTS HERE !!

[xlane]

emo 123 what u can do is...write sth like ...the paper was quite easy and u all can sole it.....give them hope.

[The Golden Girl =D]

emo 123 what u can do is...write sth like ...the paper was quite easy and u all can sole it.....give them hope.

This is your first warning.

Respecting other members  is one of the site's rules.

[xlane]

i understand.....but doesnt demoralizing students get a warning......i guess no....because its not there is SF rule right ??



By the way u moderators should help students ......and demoralizing students does not fall in the category of helping.........so i suggest u do sth about it.

[EMO123]

i understand.....but doesnt demoralizing students get a warning......i guess no....because its not there is SF rule right ??



By the way u moderators should help students ......and demoralizing students does not fall in the category of helping.........so i suggest u do sth about it.

i think you should wait for 24 hours after your paper or our paper because it is a rule you may have not read the rules or something

[xlane]

abbe yaaaar.......... ...hw does sayin the paper was easy effect the 24 hour rule....lets say an A caliber student finds the paper easy where as a C caliber student finds the paper hard.....so sayin the paper is easy or hard does not effect any rules or regulations.......if u dont understand dat much..den

[EMO123]

abbe yaaaar.......... ...hw does sayin the paper was easy effect the 24 hour rule....lets say an A caliber student finds the paper easy where as a C caliber student finds the paper hard.....so sayin the paper is easy or hard does not effect any rules or regulations.......if u dont understand dat much..den

ya that not effection by that but no disscussion of Q/A as such it is over so we should our dissussion

[Hissa]

Tomorrow is the A2 practical
what exaaaaaaaaactly do we need to know from the AS stuff?
The papers were so easy, im just worried they might get extra AS stuff 

[elemis]

Tomorrow is the A2 practical
what exaaaaaaaaactly do we need to know from the AS stuff?
The papers were so easy, im just worried they might get extra AS stuff 

There's a CIE Chemistry A2 Practical ? :S

[EMO123]

May/June 2007
Paper 04

Q-2 c)
Q-3 b)
Q-4

more doubts coming from me soon

[EMO123]

May/June 2007
Paper 04

Q-2 c)
Q-3 b)
Q-4

more doubts coming from me soon

somebody do this

[samriddh]

hello all =]
just been two days i started chem A level (both AS & A2) and any doubts i find ill be postin here...


so my first doubt,
can someone please clearly explain me what orbitals are
accordin to the definition, it says tht they are space around the nucleus where there is max. probablity of findin the electron within its orbit.
for example when n=3; l=0,1,2
so by 0,1,2 does it mean 0 from the nucleus (like coverin all the orbits in between as well> n=1 and n=2)

well orbitals are simply spaces where electrons most likely travel to while moving around the nucleus...and the number like u said n=1,2,3 etc are generally shells numbers which contain several orbitals...

it's like shells( like K,L,M,N...etc) contain subshells(1s, 2s etc where 1s means s subshell form shell no. one) now s-subshell contains 2 orbitals....

well it's my first post in this site so i dont know if u will find this much helpful but nonetheless i thought you could use some help so i posted..

[Romeesa-Chan]

May/June 2007
Paper 04

Q-2 c)
Q-3 b)
Q-4

more doubts coming from me soon

Ans 2.c- part i:
Gas A:
 16 = O
 17 = OH
 18 = H2O

Therefore, it'll be H2O

Gas B:
14 = N
16 = O
28 = N2 (14+14)
30 = NO (14+16)
44 = N2O (14+14+16)

Therefore, it'll be N2O

part ii:  NH4NO3  ?   N2O   +  2H2

Ans3.b- Not so sure.

(i) Pb is in two oxidation states: +2 and +4
The ratio will be 1:2

(ii)  Pb3O4  ?   3PbO   +   ½O2

(iii)  Pb3O4   +   4HNO3  ?   2Pb(NO3)2   +   PbO2   +   2H2O

(iv) Pb2+ more basic than Pb4+

Ans4- The d-orbital will be split in two ways: along the axis and in between the axes.

(ii) Ligands have lone pair of electrons which is how they form a covalent bond with the transition metal ion. The electrons in the orbitals pointing towards the ligands have higher energy.

c(i)- Accoring to graph and data given:
C= red and D=blue

c(ii)- More energy less wavelength. Therefore, at C.

Hope that's cleared.

[EMO123]

Ans 2.c- part i:
Gas A:
 16 = O
 17 = OH
 18 = H2O

Therefore, it'll be H2O

Gas B:
14 = N
16 = O
28 = N2 (14+14)
30 = NO (14+16)
44 = N2O (14+14+16)

Therefore, it'll be N2O

part ii:  NH4NO3  ?   N2O   +  2H2

Ans3.b- Not so sure.

(i) Pb is in two oxidation states: +2 and +4
The ratio will be 1:2

(ii)  Pb3O4  ?   3PbO   +   ½O2

(iii)  Pb3O4   +   4HNO3  ?   2Pb(NO3)2   +   PbO2   +   2H2O

(iv) Pb2+ more basic than Pb4+

Ans4- The d-orbital will be split in two ways: along the axis and in between the axes.

(ii) Ligands have lone pair of electrons which is how they form a covalent bond with the transition metal ion. The electrons in the orbitals pointing towards the ligands have higher energy.

c(i)- Accoring to graph and data given:
C= red and D=blue

c(ii)- More energy less wavelength. Therefore, at C.

Hope that's cleared.

thanx dear it really helped i can +rep after about 1 hour so i will do it in the morning now i have gtg

[Romeesa-Chan]

thanx dear it really helped i can +rep after about 1 hour so i will do it in the morning now i have gtg

Welcome. Glad to help!

Pray for my exam! (:

[EMO123]

Welcome. Glad to help!

Pray for my exam! (:

best of lucksssssssss
do your level best