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Chemistry P4| A2 only

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how do u get a ketone and a carbon dioxide in addition to 2 methyl propane...with hot concentrated KMNO4
 
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how do u get a ketone and a carbon dioxide in addition to 2 methyl propane...with hot concentrated KMNO4
i too dont get it,to explain u.. :( if anyone knowz plz help us... :(


when double bond breaks , the primary carbon forms co2 , secondary forms carboxylic acid while tertiary forms ketone.. as u can see double bond is between primary n tertiary carbon the products will be co2 n ketone!
 
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when double bond breaks , the primary carbon forms co2 , secondary forms carboxylic acid while tertiary forms ketone.. as u can see double bond is between primary n tertiary carbon the products will be co2 n ketone!
wht do u mean by primary tertiary and secondary carbon?
 
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wht do u mean by primary tertiary and secondary carbon?

primary carbon which is attached to one carbon only.. secondary which is attached to 2 carbons n tertiary which is attached to 3 carbons..

in 3 methyl propene the methyl carbon is primary as its attached to 1 carbon only so forms co2 while 2nd carbon of propene is a tertiary carbon so forms ketone!
 
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Candidates should be aware that all
β-sheets contain (roughly) the same density of hydrogen bonds – between the C=O and N-H
groups in the peptide bonds of adjacent chains. The side chains poke up and down from the plane
of the sheet. It is the interactions of these side chains between the sheets that is important for
flexibility: if these interactions are weak van der Waals (as in silk, with glycine and alanine
residues), then the sheets are flexible, If, however, the interactions are covalent S-S bridges, then
the sheets cannot slide over each other so easily, and so are more rigid.
 
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Why HFCs breakdown quickly in lower atmosphere even though C-H bond is stronger than C-Cl bond?
 
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http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s10_qp_42.pdf

This paper is kinda tough. Does anyone know the GT for this?

Meanwhile, my questions from dis papers :

2.b) Can someone explain the calculations. Again, I've said this before, WHY is lattice enthalpy positive?!
3.d)i) dafuq?? we should find out the answers by trial and error method or what/??? also include ii) plz
5.d)ii) I don't get why we need to add NaOH at the end?!

Please help me, you're sure to get a like even for trying, I'm a likaholic :D
 
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2,619
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293
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93
c
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s10_qp_42.pdf

This paper is kinda tough. Does anyone know the GT for this?

Meanwhile, my questions from dis papers :

2.b) Can someone explain the calculations. Again, I've said this before, WHY is lattice enthalpy positive?!
3.d)i) dafuq?? we should find out the answers by trial and error method or what/??? also include ii) plz
5.d)ii) I don't get why we need to add NaOH at the end?!

Please help me, you're sure to get a like even for trying, I'm a likaholic :D
5d ii.....with HCl the basic phenylamine will immediately react to for C6H5NH3+Cl-...bt we wanted just plain old phenyl amine....dats why we add NaOH
 
Messages
138
Reaction score
13
Points
28
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s10_qp_42.pdf

This paper is kinda tough. Does anyone know the GT for this?

Meanwhile, my questions from dis papers :

2.b) Can someone explain the calculations. Again, I've said this before, WHY is lattice enthalpy positive?!
3.d)i) dafuq?? we should find out the answers by trial and error method or what/??? also include ii) plz
5.d)ii) I don't get why we need to add NaOH at the end?!

Please help me, you're sure to get a like even for trying, I'm a likaholic :D
gt for this was 54! no wonder why! :p n yeah question 3 d is just trial n error type question!
 
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