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Chemistry: Post your doubts here!

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1. A and B and C
2. C and E (I thought this one was E only though)
3. E
4. C
5. C and D
6. E

Here's the marking scheme
2GLsm.jpg
thankyou so much!!
i was sure the secomd one was C only...lol
where did u get the ms frm? :/
and why cant A, B and D also be the answers for the last one?...they could replace the H atom and the -OH group ryte?
 
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Here are all the Important Chemistry Definitions for AS :)
i compiled them for quick revision because i always forget the statements of the laws and the definitions even though i have the concept.... so if anyone else has the same problem u can take help from this.... :)
Please Pray for all of us appearing in the CIE this year.... if u pray for others the Angels pray for you :) Best of Luck =)
 

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Here is a checklist of all [i hope :p ] the organic reactions of AS
if any reactions are missing please tell me too :) I have a series of mnemonics to learn them too but its kind of a long story if u still want them then inbox me :)
Best of Luck
 

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Here are all the Important Chemistry Definitions for AS :)
i compiled them for quick revision because i always forget the statements of the laws and the definitions even though i have the concept.... so if anyone else has the same problem u can take help from this.... :)
Please Pray for all of us appearing in the CIE this year.... if u pray for others the Angels pray for you :) Best of Luck =)
Here is a checklist of all [i hope :p ] the organic reactions of AS
if any reactions are missing please tell me too :) I have a series of mnemonics to learn them too but its kind of a long story if u still want them then inbox me :)
Best of Luck
cool (y)
 
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PhyZac
I made it roughly: you add the labellings + other things.
I dunno how you draw the syringe so i left it as a box
I hope u understand it.
 

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when you make titration can we start with 50cm3 as an initial reading for each rough titration
in the MS it is written that do not give marks if start with 50cm3
 

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when you make titration can we start with 50cm3 as an initial reading for each rough titration
in the MS it is written that do not give marks if start with 50cm3
 

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  • when you make titration can we start with 50cm3 as an initial reading for each rough titration.doc
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when you make titration can we start with 50cm3 as an initial reading for each rough titration
in the MS it is written that do not give marks if start with 50cm3
 

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  • when you make titration can we start with 50cm3 as an initial reading for each rough titration.doc
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when you make titration can we start with 50cm3 as an initial reading for each rough titration
in the MS it is written that do not give marks if start with 50cm3
 

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Jazak'Allahum Khairan!! :)
btw in q 26..you said that ketones can be oxidised by acidified dichromate? I don't think that's right, is it? :unsure:
ive got my notes mixed sorry :$ they dont only aldehydes change color from orange to green
 
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.
Now step by step explanation the only inorganic reactants NaBr and H2O and H2SO4. now neither Na compounds nor acids under go hydrolyses so for first stage the only reaction possible will be one given below
thenmove on to step 2 the HBr formed will react with the alcohol to form 1 bromobutane :) sulphuric acid i think catalysis the reaction
reactions
step1 NaBr(aq) +H2SO4(l)=NaHSO4(aq) + HBr(aq)
step2 HBr(aq) +CH3CH2CH2CH2OH =CH3CH2CH2CH2BR + H2O
 
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just seen the ms where does the acid come from arent we supposed to write seperate reactions for both stages
 
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Now step by step explanation the only inorganic reactants NaBr and H2O and H2SO4. now neither Na compounds nor acids under go hydrolyses so for first stage the only reaction possible will be one given below
thenmove on to step 2 the HBr formed will react with the alcohol to form 1 bromobutane :) sulphuric acid i think catalysis the reaction
reactions
step1 NaBr(aq) +H2SO4(l)=NaHSO4(aq) + HBr(aq)
step2 HBr(aq) +CH3CH2CH2CH2OH =CH3CH2CH2CH2BR + H2O
sulfuric acid is not present in the first stage :unsure: Im soooooo confused :cry: so NaBr is supposed to react with water
 
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