chemistry paper3 (AFTER EXAM DISCUSSION)

[shalado95]

I messed up in the question where they asked which compound diffuses most slowly! :?
*sigh*
But I'm soooooooo glad it's over!

 

[Ahmed-Azurus]

u know u got a point but wat is good in finishing the exam while u messed up in something

 

[Romeo10]

hey guys wat did u do in the question which said y magnesium was risen in the tube ?????
and how propanic acid's graph will be similar to the HCl graph ????

 

[Romeo10]

an how many marks should i lose in the 3 papers 1 3 6 in chemistry OL to get an A* ????

 

[Ahmed-Azurus]

gettin an A* is quiet easy
but the challenge is in gettin a very high percent which i unfortunately didnt reach
after yesterdays exam im still sad and desperate

 

[Romeo10]

gettin an A* is quiet easy
but the challenge is in gettin a very high percent which i unfortunately didnt reach
after yesterdays exam im still sad and desperate

but how many marks should i lose ... 25 marks for ex in the 3 papers

 

[Romeo10]

hey guys wat did u do in the question which said y magnesium was risen in the tube ?????
and how propanic acid's graph will be similar to the HCl graph ????

 

[Ahmed-Azurus]

mg rises because hs is produced

the graph will endup with same volume of h2 produced

 

[exampasser]

Yes the graphs will both level off at the same volume of H2.

I wrote that magnesium rises because it loses mass and MgCl is formed which is more dense than Mg so the Mg floats on the salt :S

 

[iluvchem]

the type of compound about the lipids questions.. (glycine sterate)

answer was

type of compound:Fatty acid (soduim stearate)
use:soap

becuase fats or lipids on hydrolisis u get fatty acids and glycerol

 

[Saturation]

Quick doubts:

Which experminet was faster? The one which was with copper right?
And why was it that experiment?? I wrote cause copper conducts heat better than plastic :roll:

The balacing of the final equation? (methanoic acid + calcium carbonate)? I just guessed... :shock:

For the type of compound i wrote:
Type :Stearate
Use: Soap
Is that right???

For obtaining Cl2 (seaweed), i wrote CFC's! :? It didn't click to me about NaCl!

The difference in physical properties between CO2 and SiO2 = SiO2 will be harder and have a higher melting point than CO2?

And finally the last last question. (4 th acid in the homologus series)
Name : Butanoic acid
Molecular formula : C3H7COOH
Emperical formula: C2H4O

Is this correct?? :?:

Hopefully we'll all get our A*'s!

 

[shalado95]

Quick doubts:

Which experminet was faster? The one which was with copper right?
And why was it that experiment?? I wrote cause copper conducts heat better than plastic :roll:

The balacing of the final equation? (methanoic acid + calcium carbonate)? I just guessed... :shock:

For the type of compound i wrote:
Type :Stearate
Use: Soap
Is that right???

For obtaining Cl2 (seaweed), i wrote CFC's! :? It didn't click to me about NaCl!

The difference in physical properties between CO2 and SiO2 = SiO2 will be harder and have a higher melting point than CO2?

And finally the last last question. (4 th acid in the homologus series)
Name : Butanoic acid
Molecular formula : C3H7COOH
Emperical formula: C2H4O

Is this correct?? :?:

Hopefully we'll all get our A*'s!

I might not be the best person answering this... but here goes

Yes, it was the one with copper... BECAUSE.. copper is a transition metal and acts like a catalyst. (dnt worry, I made the same mistake! )

About the equation.. I don't really remember!

Compound, I wrote fatty acid... like a moron... whc is wrong!
But the use I think is right... making of soaps!

The sea weeds are in the sea.. and sea is salty... NaCl.. so chlorine come from there!

Yes...the physical properties you mentioned are right!

 

[niassu]

well i thought the exam was nice but unfortunately i have made many mistakes

 

[SuperXDE]

well i thought the exam was nice but unfortunately i have made many mistakes

Eh , it is just an exam , not a life or death matter .. Just cheer up , you've finished the exams , you are on holiday now .. ( till the results come out ¬¬ that holiday might end )

I've totally screwed up a whole page in the exam , about the Ester thing , I "fribbled" anything in it

 

[coolguy]

Who did the second variant here.......i dont remember seeing the copper question at all! did i miss a page or something?

 

[imkillinit]

See guys there was a question about the photochemical reaction which was thallium something ,... OK
Then they name another halide compound and state the use of it

Question was

Name ........................................
Use ....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................

So idont know which variant but i know i did this in U.A.E and some one can tell me the answer PLZ az quick ly as possible
PLEZ i am really worrid

 

[XPFMember]

I think this is the second variant,anyway confirm it by checking ur statement of entry is it 32 31 for chemistry P3?

 

[imkillinit]

See guys there was a question about the photochemical reaction which was thallium something ,... OK OKKAY MY PAPER IS 32 second variant
Then they name another halide compound and state the use of it or some thing like that

Question was

Name ........................................
Use ....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................

So idont know which variant but i know i did this in U.A.E and some one can tell me the answer PLZ az quick ly as possible
PLEZ i am really worrid