Author Topic: Chemistry Paper 1  (Read 6418 times)

Offline Naruto

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Chemistry Paper 1
« on: June 07, 2009, 03:01:10 pm »
hey
When i was going through the papers i didn't got the answer for the following questions and i guess the answers that i have are wrong so  can anyone tell me the answer and explian it too. Thanks :)

The answers that i have are:
16 is D
19 is C
39 is B

If you think these answers are correct then plzz explain and if not then what is the right answer? and again explain :P

I have attached the questions

Offline Wahab09

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Re: Chemistry Paper 1
« Reply #1 on: June 07, 2009, 03:49:19 pm »
16 i aint sure of but i say its
B

19 is definatly B as it contains an iodide which turns yellow.
39 is C as the number of molecules havent changed.. 2 carbons which weigh 12 and 4 hydrogens = Mr of 28
and the same thing for polyethene the Mr hasnt changed.

Offline esso

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Re: Chemistry Paper 1
« Reply #2 on: June 07, 2009, 11:20:13 pm »
16 i aint sure of but i say its
B

19 is definatly B as it contains an iodide which turns yellow.
39 is C as the number of molecules havent changed.. 2 carbons which weigh 12 and 4 hydrogens = Mr of 28
and the same thing for polyethene the Mr hasnt changed.

please dont answer if ur not sure of ur answers.....16 is D
19 is B
39 is B.....100 percent sure

Offline susman

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Re: Chemistry Paper 1
« Reply #3 on: June 08, 2009, 01:05:48 am »
19 is B 39 is B
and as for the 16 part my guess is that it isC
It cant be D because the time has started but the reaction hasnt..
it cant be A because th reaction has to slow down to come on an end
it cant be B because the speed of reaction is greatest when the aprticles have most energy/concentration..
so it is C (i guess)

+ rep if u like it
bcoz already mine is in minuses

Offline shafeeqshazana

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Re: Chemistry Paper 1
« Reply #4 on: June 08, 2009, 03:12:33 am »
nope.
16 is b
19 b
39 b

without doubts

zara

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Re: Chemistry Paper 1
« Reply #5 on: June 08, 2009, 06:36:01 am »
nope.
16 is b
19 b
39 b

without doubts
can u plz explain ur answers to 16 and 39

Thanks..

Offline Depriviated

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Re: Chemistry Paper 1
« Reply #6 on: June 08, 2009, 07:37:40 am »
are u guys talking about chem p1 09 june or some other
if u are i would like to tell u plz dont leak answers

zara

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Re: Chemistry Paper 1
« Reply #7 on: June 08, 2009, 07:58:58 am »
are u guys talking about chem p1 09 june or some other
if u are i would like to tell u plz dont leak answers

ooyyeee....these r past pprs ques...v hv doubt in it...
no one has don't chem p1 newhere in the world...its on 10th for everybody...

so plz if u cn explain id aapreciate...Thanks..

Offline mayyoya92

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Re: Chemistry Paper 1
« Reply #8 on: June 08, 2009, 12:59:00 pm »
16 is d for sure ,because during explosions very strong heat is released immediately and not gradually . so it increase and after explosions it decreases again

Offline Wahab09

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Re: Chemistry Paper 1
« Reply #9 on: June 08, 2009, 05:19:44 pm »
guys.. how the hell is 39 B..
its C for sure..

how the hell can u even get an empirical formula without knowing the % and stuff..

molecular formula is the same..
c 12 and c 12 make 24
h-h-h-h= 4

24+4 = 28..

the same with polyethene!

Offline idk

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Re: Chemistry Paper 1
« Reply #10 on: June 08, 2009, 05:47:39 pm »
ok well first 19 should be K2SO4 as yellow ppt produce by sulphur.
 16 according to me should be B as first the explosion reaction will cause inc. in rate of RX but then reaction will stabilise but continue at a certain speed.this can be seen in nuclear reactors too and thats why boron rods are put to regulate the speed of reaction.39 i think should be B as no matter what happens there will be 2 atoms of c and 4 atoms of h in 'n' number of molecules too.hope this helps.

nid404

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Re: Chemistry Paper 1
« Reply #11 on: June 08, 2009, 06:39:03 pm »
19 is B
39 is B
16 is D(after a lot of research on explosion and reaction rate)
« Last Edit: June 08, 2009, 06:50:01 pm by nid404 »

Offline Ghost Of Highbury

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Re: Chemistry Paper 1
« Reply #12 on: June 08, 2009, 06:46:27 pm »
i think the 39 answer is B
In an addition polymerisation unsaturated monomer units react together to form a polymer with essentially the same empirical formula as the monomer
divine intervention!

Offline Ghost Of Highbury

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Re: Chemistry Paper 1
« Reply #13 on: June 08, 2009, 06:50:18 pm »
for the 16th one i think its (b)
divine intervention!

Offline jennie

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Re: Chemistry Paper 1
« Reply #14 on: June 08, 2009, 06:56:01 pm »
16 = C
19 = B
39 = B