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Chemistry Paper 4-theory- doubts =D

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yea i know that...bu-ut for 8 marks i donno how to elaborate...ESP! 'How the catalyst u've chosen helps to decrease the Ea! Please
Jazak allah Khair ! May Allah bless u! :D
4 marks for each example
1 mark for example
1 mark for telling which type of catalysis it is
1 mark for reaction equation
1 mark for what Cat is doing (except meeeow :p )
u got the first three i hope so
for the last mark in both example:
a(Iron here is used as increasing the surface area where reagants are adsobed on its surface to increast the number of efficient collisions ...)
b(If Fe2+ is used it will reduce to Fe3+ bu oxidizing peroxydisulfide(s2o8)^2-
the Fe3+ ion now convert I- ions to I2 guys and Fe2+)
for b: the reaction in water is over all slow so homogenous catalysis(Fe2+) introduced to fasten the reaction by stated above(at the end u get Fe2+ ions back)
hope this helps please pray for me :)
 
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Assalamu 'Alaykum wa Ra7matullah everyone...
I'm very deeply sorry I couldn't answer your questions...please forgive me :(
It's just that something went wrong with my application process...and that kinda ruined my day and got me busy.
Please pray that i get accepted to uni...and once again, I'm really very sorry for not answering your questions....
 
Messages
345
Reaction score
394
Points
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4 marks for each example
1 mark for example
1 mark for telling which type of catalysis it is
1 mark for reaction equation
1 mark for what Cat is doing (except meeeow :p )
u got the first three i hope so
for the last mark in both example:
a(Iron here is used as increasing the surface area where reagants are adsobed on its surface to increast the number of efficient collisions ...)
b(If Fe2+ is used it will reduce to Fe3+ bu oxidizing peroxydisulfide(s2o8)^2-
the Fe3+ ion now convert I- ions to I2 guys and Fe2+)
for b: the reaction in water is over all slow so homogenous catalysis(Fe2+) introduced to fasten the reaction by stated above(at the end u get Fe2+ ions back)
hope this helps please pray for me :)
for the last one, it's slow cause they both r anions ...that's a right reason too eh?
May Allah bless u mate!! evn if u dnt ask me, I do remember everyone in my prayers... Jazak Allah Khair! :D btw any tips for app? :(
Cheerio!
 
Messages
345
Reaction score
394
Points
63
4 marks for each example
1 mark for example
1 mark for telling which type of catalysis it is
1 mark for reaction equation
1 mark for what Cat is doing (except meeeow :p )
u got the first three i hope so
for the last mark in both example:
a(Iron here is used as increasing the surface area where reagants are adsobed on its surface to increast the number of efficient collisions ...)
b(If Fe2+ is used it will reduce to Fe3+ bu oxidizing peroxydisulfide(s2o8)^2-
the Fe3+ ion now convert I- ions to I2 guys and Fe2+)
for b: the reaction in water is over all slow so homogenous catalysis(Fe2+) introduced to fasten the reaction by stated above(at the end u get Fe2+ ions back)
hope this helps please pray for me :)
One more thing. http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_qp_41.pdf
Q3 b) do we have to mention NO+1/2O2 in the middle of the two mountains? :)
 
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652
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2,822
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well i did! :p
its like the same reaction as with alkene
with nickel above 160 - 200*C
70-80 atm
Benzene blows offff
now it turns to cyclohexane ==> c6H12
Sorry to disturb you again but one thing more for the same Q3)e) why is benzene reacting with excess Br(aq) if any catalyst of FeBr2 isnt present :confused: ?
knowitall10 if u know plzz help me with this :(
 
Messages
2,865
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Sorry to disturb you again but one thing more for the same Q3)e) why is benzene reacting with excess Br(aq) if any catalyst of FeBr2 isnt present :confused: ?
knowitall10 if u know plzz help me with this :(
I'll be pleased to help:) Please tell me which question..
 
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it's excess Br2...u use a catalyst when it's not in excess i think. I would take the word "excess" as a hint that no catalyst is needed...
so this means whenever excess Br(aq) is mentioned it will always react with benzene ring as well so no catalyst of FeBr2 will be required ?
 
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I just saw the ms n one thing is not clear that is y they used Na when it is not mentioned ! I m cnfused wid dt nw 2!

N abt the ans in 5c yes!

:) NO problem!the pleasure is mine! Just pray 4 me really worried with chem! :(
 
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I just saw the ms n one thing is not clear that is y they used Na when it is not mentioned ! I m cnfused wid dt nw 2!

N abt the ans in 5c yes!

:) NO problem!the pleasure is mine! Just pray 4 me really worried with chem! :(
me too. :( imma pass out anytime. anyhow, bu-ut it's aqueous alkaline NaOH ehh? is that the reason!? o_O
 
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May b so .... cz NaOH is alkali but still not justified cz its nt mentioned! they gotta mention to draw dat conclusion!!!

me too. :( imma pass out anytime. anyhow, bu-ut it's aqueous alkaline NaOH ehh? is that the reason!? o_O
 
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