Chemistry AS Paper 2 Variant 1

[princeunknown]

Anyone doing Variant 1 besides in KSA? Any tips or hints?

 

[allo0oaa]

I am doing it on kw. It's so hard

 

[1992]

which part u find it hard??

 

[allo0oaa]

U did it ??

 

[1992]

it going to enter exam now! bie

 

[allo0oaa]

it was hard !!!!

 

[1992]

last question was horrible :S i didnt know wat to put.
Also what was the sensible answer for volume of NAOH

 

[Vlad]

O YES 1992.
ORGANIC WAS BIT TRICKY.
IM LOOSING FEW MARKS IN ORGANIC.

 

[Uranium-238]

Hey, I need answers for P21...
1)reaction kinetics....y the reaction rate for hydrolysis of halogenoalkane is less than for neutralisation reaction?
2)y can If7 be formed instead of Clf7!

Alhamdullilah the paper was good...but there is Paper 4 remaining, the toughest paper containing applications which is beyoond our knowledge....MAY ALLAH HELP US (AMEEN)!!!

Answer soon!!!

 

[TravisMcDee]

Im not entirely sure of what i said but it went alng the lines of this
1) The Mechanism for the nucleophilic/electrophilic , substitution of the -OH group onto the Br takes time for then to disassociate and switch with one another , the acid base reaction im not really sure i just said its a simple molecular reaction forming a salt and water , and therefore is immediate
2) The ClF7 does not exsist has the elctronegativity difference between the two molecules is to little and would not hold , where as the IF7 would as there electroneativitys are greater ...

Not really sure , but im pretty sure ...

 

[farah]

we took variant 1 in egypt too...i wrote the same answers as TravisMcDee and i also mentioned the high activation energies required for the hydrolysis of halogenoalkanes.....

 

[1992]

Does anyone remember the one of circlering the pair of electrons?? which ones were they??
the first diagram i put the 2 electrons from the left
the second diagram, i put the 2 centre electrons
and the last diagram i put the 2 electrons from the right
are they correct??

 

[Uranium-238]

Does anyone remember the one of circlering the pair of electrons?? which ones were they??
the first diagram i put the 2 electrons from the left
the second diagram, i put the 2 centre electrons
and the last diagram i put the 2 electrons from the right
are they correct??

here r the answers....
the one with cordinate bond is XX
covalent bond is 2 "0X"
lone pair is "OO" and "XX"

 

[1992]

oo and xx??? or just oo?

 

[Uranium-238]

the question says to circle covalent bond, lone pairs....its better to circle both 00 and XX because we v to define all the electons in the outer shell!!!

 

[1992]

didnt it say draw one pair of electrons in each diagram?? i remembered it saying so, thats y i only cirlcled one pair
well now not sure :s

 

[ghgirl]

the question about reaction one and two was about a multistep reaction with the slowest step having a high activation energy but fr reaction two it was a single step reaction with a low activation energy
for the oxide i did OF6...yh and the 8 atoms is S
pretty cool loved the organic....
for the last question you had to use mole ratio between NaOH and W ...
cant w8 for paper 4 eventhough im sure it'd be very hard!!!!!