CHEM PAPER-22

[Vlad]

almost every wrote different ans..........

 

[tricky]

yaaa sandy it was CARBON....wat did u ryt abt the part next to carbon of putting tube away before it gt cool i thnk qs was lyk that dnt knw exact...

 

[vux]

ohki hehe my answer to tht black solid wuz the the Al2O3 present is heated nd it gets reduced forming Al nd its black..
ok did ny1 lse have difficulty in making the last isomer...well i did..nd which one cud nt be F..i wrote S coz it wud hydrolyse to form a secondary alcohol which wud form a ketone which duznt answer the tollens test..lol...duz it make sense??
overall paper wuz very good!

same for me. only S is an aldehyde. the other 3 isomers i could figure out were ketones. dont know if its correct or not though.

 

[tricky]

vux S in nt a aldehyde its ketone...

 

[tricky]

other 3 isomers were ALDEHYDE...

 

[Sabrina]

it was S, because it would form secondary alcohol n would form ketone..
and the black thing was carbon.

 

[JT ite]

The black thing was definitely carbon soot, formed as a by product of the elimination reaction
paper was quite easy

 

[fzum12_13]

hey guyz was there any energetics question???????????????
or about equilibrium???????????????????
plz reply fast

 

[wadha]

how was da organic chem part???????????????????

 

[fancraze43]

oh crap the black thingy is carbon??? but how??
newez i wrote Iodine......you see it's shiny grey-BLACK solid
hehehe
yupz i too wrote 'S' and other isotopes which i made all gives primary alcohol when oxidized....btw what's the condition for polymerization??? i wrote heat...LOL

 

[wadha]

plzzzz can sme reply soon(((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((99

 

[bilal_92]

i wrote da black thing CUO!!!its black too!!!formed cuz of da reaction btwn da products of combustion of alchol nd minerals!!!!

but is it correct???


nd was it NAOH (aq) da answr to da hydrolysis of setrx part?

 

[bilal_92]

esters*

 

[umer khan]

i wrote da black thing CUO!!!its black too!!!formed cuz of da reaction btwn da products of combustion of alchol nd minerals!!!!

but is it correct???


nd was it NAOH (aq) da answr to da hydrolysis of setrx part?

nope CU is foremd cuz of in-complete combustion
nd it should have been an acid since there was an acidic hydrolisis to make a alcohol in ester part......

 

[aristotle]

who claims carbon to black , i take diamond and i suggest it's made of carbon , that might be black ..why not adopt poor graphite , that's grey black sold ! well , hmm.. agreed
BUT HAD YOU PEOPLE REALIZED THAT THE QUESTION WAS RATHER AN MCQ WHOSE OPTIONS WERE GIVEN IN THE LATER PART i.e pumice bla bla and the correct answer was pumice indeed ! :twisted: strong heating causes to it to "BLACKEN"

 

[angel101]

@ vlad carbon is always black everyone knows that
soot is another way of saying carbon so i dont think so.

 

[ashhadazam]

OK guyz... !!!
The black solid was COPPER(ii)OXIDE for sure !!!!
Copper reacts with air to give black CuO and i am damn sure about this one !!

 

[ashhadazam]

And it just wasnt carbon... Lol
How can it be carbon.. it was a catalyst.. If carbon had to be deposited it should have been deposited at eh bottom of the tube where the alcohol was not the middle..

it couldnt be H2SO4. it was a solid
It couldnt be Al2O3 because it dosnt go further reaction with air and it isnt black
It isnt SiO2.. very heat resistant.. no effedct on heating

 

[ashhadazam]

Well it could be either acid or NaoH.. !!! they said specify a NECESSARY REAGENT (not reagents) for the hydrolysis..

 

[ashhadazam]

And u dint have to write pumice .. U had to name the compound which was AL2O3