GT for Chemistry paper 22 AS.

[robotic94]

i wrte phsohrus..bt cut it n wrte Na...whch is right??

we had to write any one right, just asking, because i dont rem, i think i wrote sulfer as well for this!

 

[xxfarhaxx]

Lol yes this is the only paper i remember what ever i wrote because my chem practical sucked and so i had to do this very well. so i checked it like so many times
but you see i still got -127 pffth

wel atleast u will mrks fr da sign!!!

 

[SalamH]

ppl 4 Al and Cl did you'll write AlCl3 or Al2Cl6? I wrote AlCl3

 

[Bulltyro]

alcl3

 

[AdeelRox]

oops sorry guys it was q.4 in which when G was oxidised in the last part with k2cr2o7 we got triol,with 3 OH fuctional groups. i made the whole structure showing every bond. did we had to draw the displayed structural formula
or the structural formula?

 

[thunderingthunder]

ppl 4 Al and Cl did you'll write AlCl3 or Al2Cl6? I wrote AlCl3

I also wrote AlCl3

 

[saurabh]

P22
stuffs i remember!
q1: phosphorus has coloured flame!
observations wer white solid formed and color of chlorine disappears.
all the three were acidic(pH na: 3, and others i dont remember) and i did all of them react(which i know is wrong )
reaction with water, neutralisation?
angle a was smaller bcause it had 2 lone pairs
q2: enthalpy i think i did a silly mistake and i THINK i got -127
reaction kinetics for all the three!
q3: 2 esters were formed
one alkene
one alcohol
and one carboxylic acid

dehydration, oxidation, hydrolysis/hydration

chiral one was easy
cis trans skeletal was easy

q4: 2 ticks for alcohol for oxidising agent (i dnt rem what was it) and Na
1 tick for Nahco3 and ester
1 tick for Carboxylic acid and Na
1 tick for aldehyde and oxidising agent

functional grp was alcohol

no. of moles of hydrogen= 0.05 (LOL i m pretty sure im wrong, i just didnt want to leave the space empty so did some shit and got 0.05)

then it was ketone which doesnt react with fehlings but with 24 DNPH
and there were 2 alcohols and one ketone, so i got C3H6O3
and the last with oxiding agent the primary alc turn into carboxylic acids
the ketone tunrs into sec alcohol with the reducing agent

THATS IT i cant rem 2 or 3 parts in there!
point me out if im wrong or if i left something!
God Bless You All!

i can see some mistakes here

 

[robotic94]

i can see some mistakes here

urmm like?

 

[Pals_1010]

I hadn't notice it was SKELETAL formula that was asked for the cis-trans isomer(silly mistake I know) but I saw it like when 5 mins was left, and I hastily drew these. Do you think I'll get my marks?

 

[aom]

ppl 4 Al and Cl did you'll write AlCl3 or Al2Cl6? I wrote AlCl3

Both are correct

 

[good man12]

. let me tell my answers......
1)a) Phosphorus
b) Sodium
c)2Al(s)+3Cl2(g)=2AlCl3(s)
obs : pale green colour of chlorine fades....white solid formed
d) Argon is inert gas and has complete octet.
2)a) Nacl = dissolves = ph7
AlCl3=reacts = pH (1-3)
Silicon= reacts = pH (1-3)
b) reaction = hydrolysis
c) sulphur =2 lone pairs
nitrogen = 1 lone pair
d) angle a will be smaller as sulphur has 2 lone pairs which will exert greater repulsive force on bonding electrons( reducing angle).
3) Ch3OH(l)+3/2O2(g) = CO2(g) + 2H2O(l)
enthalpy change which takes place when 1 mole of substance is completely combusted in excess O2 under standard conditions
b) -129kJ mol-1
i) rate increases = frequency of collisions increase= more effective collisions
ii) rate increaeses, particles have more kinetic energy , more energetic collisions, more effective collisions , more particles with Ea
iii) rate increases...Ea lowered, more particles has Ea....effective collisions greater

3) I CH3COOCH(COOH)CH2COOH
II)CH3OOCCH2CH(OH)COOCH3
III HOOCCH=CHCOOH
IV) HOOCCH2CH(OH)COOH
V) HOOCCH(OH)CH(OH)COOH
VI) HOOCCOOH

a) dehydration
b) oxidation
c) hydration/addition

d) optical iso
e) is trans iso
f) emperical : C1H1.3333O1.165 this was simplest then multiply with 6 to get whole numbers : C6H8O7

4) was too simple....

 

[good man12]

I hadn't notice it was SKELETAL formula that was asked for the cis-trans isomer(silly mistake I know) but I saw it like when 5 mins was left, and I hastily drew these. Do you think I'll get my marks?

u will get 1 mark, u had to make skeletal formula in which u dont write C and H.....

 

[Pals_1010]

u will get 1 mark, u had to make skeletal formula in which u dont write C and H.....View attachment 10378

Dang.... And I was hoping for full marks .... Nevermind thanks there and do you remember how many marks that question was for? 2 or 3 marks?

 

[Saad Sarfraz]

Guys the reaction of aluminium with chlorine i made AL2CL6 intead of AlCL3 how many marks do u think will be deducted? I personally think the examiner is gona allow this answer too

 

[good man12]

3 marks = optical.......3=skeletal ...3= emperical.....3= reactions.....1= esters use.....6= chart or reaction....total =16

 

[good man12]

Guys the reaction of aluminium with chlorine i made AL2CL6 intead of AlCL3 how many marks do u think will be deducted? I personally think the examiner is gona allow this answer too

Al2Cl6 exists in vapour phase only...and at standard conditions.... AlCl3 prevails.....so i think it was AlCl3 (s).....

 

[Pals_1010]

Guys the reaction of aluminium with chlorine i made AL2CL6 intead of AlCL3 how many marks do u think will be deducted? I personally think the examiner is gona allow this answer too

they will allow...

 

[Saad Sarfraz]

Okay guys to settle one thing the question on the formation of methanol Whether it was reversible or not we had to just tell in general how the temp. pressure and catayslt affect it. But ive got a doubt they wrote the temp. as 600K so i converted it too 327C and well thats a low temp. So i wrote the temp given to the reaction is low (not as high as other commercial processes) this will decrease the rate of formation because the average kinetic energy of the molecules decrease. Do u think he'll except this ?

 

[vishal]

Guys for the reaction part in Q 3 i wrote Elimination, oxidation and addition.....Are they correct?

 

[TheMan123]

we had to write any one right, just asking, because i dont rem, i think i wrote sulfer as well for this!

I think the answer is Na. Na burns yellow in flames. The question asks which element burns I think not which chloride. I did paper 22 by the way