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ALL CIE CHEMISTRY DOUBTS HERE !!

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EMO123:

--- Quote from: Fidato on May 06, 2011, 05:53:19 am ---H2O (2 bonding pairs, 2 lone pairs) = 104.5o
CH4 (4 bonding pairs) = 109.5o
NH3 (3 bonding pairs, 1 lone pair) = 107o
SF6 (6 bonding pairs. S has 12 electrons now, after bonding) = 90o
CO2 (linear) = 180o
BF3 (3 bonding pairs. Look at the number of electrons in the outer shell of B after bonding !) = 120o

Do the rest yourself, you may find answer as D.

--- End quote ---
are you shure :-\

I like cheese:
So ive done almost all the past papers...and now the qns which i dont know how to do have piled up

http://www.xtremepapers.me/CIE/index.php?dir=International%20A%20And%20AS%20Level/9701%20-%20Chemistry/&file=9701_w05_qp_1.pdf

(Oct/Nov 2005 paper 1)
qn. 7,12,16,25

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http://www.xtremepapers.me/CIE/index.php?dir=International%20A%20And%20AS%20Level/9701%20-%20Chemistry/&file=9701_w04_ms_1.pdf

(Oct/Nov 2004 paper 1)
Qns. 3,7,10,12,18, and why isnt the answer to Qn 27 Option B ???
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http://www.xtremepapers.me/CIE/index.php?dir=International%20A%20And%20AS%20Level/9701%20-%20Chemistry/&file=9701_s06_qp_1.pdf

(May/June 2006 paper 1)

Qn 2,38
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not asking someone to do it all but if a couple of people could do 1 or 2 qns at a time that would be awesome  ;D ;D ;D ;D ;D ;D ;D ;D :P

Master_Key:

--- Quote from: I like cheese on May 06, 2011, 08:58:09 am ---So ive done almost all the past papers...and now the qns which i dont know how to do have piled up

http://www.xtremepapers.me/CIE/index.php?dir=International%20A%20And%20AS%20Level/9701%20-%20Chemistry/&file=9701_w05_qp_1.pdf

(Oct/Nov 2005 paper 1)
qn. 7,12,16,25

-----------------------------------------------------------------------------------------------------------------------------------------

http://www.xtremepapers.me/CIE/index.php?dir=International%20A%20And%20AS%20Level/9701%20-%20Chemistry/&file=9701_w04_ms_1.pdf

(Oct/Nov 2004 paper 1)
Qns. 3,7,10,12,18, and why isnt the answer to Qn 27 Option B ???
-----------------------------------------------------------------------------------------------------------------------------------------

http://www.xtremepapers.me/CIE/index.php?dir=International%20A%20And%20AS%20Level/9701%20-%20Chemistry/&file=9701_s06_qp_1.pdf

(May/June 2006 paper 1)

Qn 2,38
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not asking someone to do it all but if a couple of people could do 1 or 2 qns at a time that would be awesome  ;D ;D ;D ;D ;D ;D ;D ;D :P

--- End quote ---

(Oct/Nov 2005 paper 1)
qn. 7,12,16,25

7. Strong acid-strong base will have maximum negative change in enthalpy and Weak-Strong will have lower. So ans is A.

12. MgO = 1:1
     Al2O3 = 2:3
     SO2= 1:2

Plot your graph and you will get D.

16.Colourless gas = CO2 So a carbonate is sure. MgO and Bao react vigorously.

25. 2,4-dnph reacts with aldehydes.

I like cheese:

--- Quote ---(Oct/Nov 2005 paper 1)
qn. 7,12,16,25

7. Strong acid-strong base will have maximum negative change in enthalpy and Weak-Strong will have lower. So ans is A.

12. MgO = 1:1
     Al2O3 = 2:3
     SO2= 1:2

Plot your graph and you will get D.

16.Colourless gas = CO2 So a carbonate is sure. MgO and Bao react vigorously.

25. 2,4-dnph reacts with aldehydes.
--- End quote ---

ok thanks man but ummmm for qn 25, in both options A and D , there is 1 aldehyde......so which one??? and does a carboxylic acid react with PCl5??

EMO123:
master_key
2,4-dinitrophenaylhydrazine also reacts with ketones to give a deep yellpw pr orange precipitate

there fore
y is a aldehyde
so there is only one aldehyde not ketone also present in that combination

:. D is the right answer

hope i helped

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