Author Topic: CHEMISTRY PAPER 1 HERE  (Read 38451 times)

Offline unknown

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Re: CHEMISTRY PAPER 1 HERE
« Reply #195 on: June 11, 2009, 04:24:44 pm »
will someone explain to me question 11 november07
hey lsn d ans is b
d eq is like 1mol of org. + 8mol of 02
so c6h90h+ 8o2= 6co2+ 5h20

Offline XGhostX

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Re: CHEMISTRY PAPER 1 HERE
« Reply #196 on: June 11, 2009, 04:29:54 pm »
Can any one give me any tips to do with chemistry, its the hardest subject ever  :( :'(
XD

Offline Aishath

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Re: CHEMISTRY PAPER 1 HERE
« Reply #197 on: June 11, 2009, 04:30:53 pm »
Can someone help me for ques. 36 in OCT/NOV 1997?
can u send me the paper i dont have it or atlst write the comp que
Well i ll write the ques.
"Which structure is that of an alkane?
A.Ethanoic acid
B. Propanol
C. Ethyl Ethanoate
D. Pentane"

Offline sweetie

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Re: CHEMISTRY PAPER 1 HERE
« Reply #198 on: June 11, 2009, 04:31:22 pm »
cn any1 plz attach chem ppr 1 oct08????????

Offline girl_92

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Re: CHEMISTRY PAPER 1 HERE
« Reply #199 on: June 11, 2009, 04:31:35 pm »
Can someone help me for ques. 36 in OCT/NOV 1997?
can u send me the paper i dont have it or atlst write the comp que
Well i ll write the ques.
"Which structure is that of an alkane?
A.Ethanoic acid
B. Propanol
C. Ethyl Ethanoate
D. Pentane"

pentane
some people sleep to dream while othrs wakeup to follow dem im the second type how abt u

Offline girl_92

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Re: CHEMISTRY PAPER 1 HERE
« Reply #200 on: June 11, 2009, 04:32:09 pm »
cn any1 plz attach chem ppr 1 oct08????????
download it frm freeexampapers.com
some people sleep to dream while othrs wakeup to follow dem im the second type how abt u

Offline Aishath

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Re: CHEMISTRY PAPER 1 HERE
« Reply #201 on: June 11, 2009, 04:34:08 pm »
Quote
pentane

Ya well thats wat i thought too bt the mark scheme says its ethyl ethanoate :-\
so that means the mark scheme is wrong???

Offline noor92

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Re: CHEMISTRY PAPER 1 HERE
« Reply #202 on: June 11, 2009, 04:34:39 pm »
Can someone explain Nov 03 Q 16 aaanndd Jun 04 Q15? Thanks

Offline girl_92

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Re: CHEMISTRY PAPER 1 HERE
« Reply #203 on: June 11, 2009, 04:35:43 pm »
Quote
pentane

Ya well thats wat i thought too bt the mark scheme says its ethyl ethanoate :-\
so that means the mark scheme is wrong???
lemme chk this out it cannot be ethl ethanoate wait a sec
some people sleep to dream while othrs wakeup to follow dem im the second type how abt u

Offline astarmathsandphysics

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Re: CHEMISTRY PAPER 1 HERE
« Reply #204 on: June 11, 2009, 04:39:48 pm »
Can someone help me for ques. 36 in OCT/NOV 1997?

An alkene is a hydrocarbon with a C=C double bond

B

Offline girl_92

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Re: CHEMISTRY PAPER 1 HERE
« Reply #205 on: June 11, 2009, 04:41:42 pm »
Quote
pentane

Ya well thats wat i thought too bt the mark scheme says its ethyl ethanoate :-\
so that means the mark scheme is wrong???
lemme chk this out it cannot be ethl ethanoate wait a sec
it cannot be if consider it on the basis of a single bond den all of dem have single bonds even the basic formula of CnH2n+2 doesnt apply den how is it possible
some people sleep to dream while othrs wakeup to follow dem im the second type how abt u

Offline unknown

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Re: CHEMISTRY PAPER 1 HERE
« Reply #206 on: June 11, 2009, 04:42:25 pm »
Can someone explain Nov 03 Q 16 aaanndd Jun 04 Q15? Thanks
bond breaking endo n bond formin exo
thts y x n y bond break so weak  as d reaction exo i hope u get it n as far d other q in y it has 2 be more  as its excess so y inc. hm me 2 also dnt knw hw 2 explain tht bt i hope u gt d other 1

Offline Aishath

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Re: CHEMISTRY PAPER 1 HERE
« Reply #207 on: June 11, 2009, 04:44:58 pm »
Quote
lemme chk this out it cannot be ethl ethanoate wait a sec
it cannot be if consider it on the basis of a single bond den all of dem have single bonds even the basic formula of CnH2n+2 doesnt apply den how is it possible
[/quote]
I have no idea.....
i think the mark scheme is wrong cos many times it happened to the other papers....
So the ans. should be pentane

Offline astarmathsandphysics

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Re: CHEMISTRY PAPER 1 HERE
« Reply #208 on: June 11, 2009, 04:46:08 pm »
Can someone explain Nov 03 Q 16 aaanndd Jun 04 Q15? Thanks

Nov 03 Q 16 decreases since hydrogen is lighter than oxygen and  increases

Jun 04 Q15 C since weak bonds take little energy to break and strong bonds give out a lot of energy when they are made


Offline girl_92

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Re: CHEMISTRY PAPER 1 HERE
« Reply #209 on: June 11, 2009, 04:47:04 pm »
Can someone explain Nov 03 Q 16 aaanndd Jun 04 Q15? Thanks
the second que goes like this
energy required to break the bonds - energy required to form bonds
so if the bonds are weaker less energy will be required to break dem n if the bonds formed r strong den more energy will be required to form dem n thus the answer u get will be neative indicating it is exo
some people sleep to dream while othrs wakeup to follow dem im the second type how abt u