Comparison of Multiple-Choice Answers (1 Viewer)

[s2indie]

lol, it looks like i got 9-10/15.
hahah i got 5/15 for my trials.

 

[CheekyPunk]

1.C
2.A
3.B
4.C
5.B
6.B
7.A
8.B
9.C
10. A? Too much work for one mark =P
11. can't remember. I think
12.A
13.D
14.C - Probably D... since the results were to 3 dp..
15.A

Dang... that sucks. i shouldnt have looked in this thread >.<

 

[dleroy]

(quote)Would someone be able to explain the working behind question 6, sorry.(/quote)

Well... i think the glucose monomer for cellulose has 5 O atoms, 10 H and 6 C.. so simply you just add them all up 16x5 + 10x1 + 6x12 (which is the weight for 1 monomer) and multiply it by 5 (since there are 5 monomers.) which is equal to 810.

Kind of sure....

1) C
2) A
3) B
4) C
5) B (definately only 4)
6) A (DEFINATELY 810... cuz there is 5 OXYGEN atoms and 6 carbon atoms and 10 H atoms in a glucose monomer for Cellulose.... ???)
7) A (definately have a sweet smell)

50% sure...

8) B
9) A
12) A
13) D
14) B

Eeni minee mo... (is that how you spell it?)

10) B
11) C
15) A

 

[sando]

sorry but.. 9 is definetly not A .. and 14 is definetly not B

 

[angmor]

tell me what i got wrong
i got

1C
2A
3B
4C
5B
6D
7A
8B
9B
10A
11A
12A
13D
14C
15A

 

[CheekyPunk]

6 is B i think
Glocose-Glocose-Glocose-Glocose-Glocose
5 x 180 = 900
900 - (4x18) for the four water molecules formed from the condensation reaction.
= 828

???

 

[ringout13]

14 is B definately, u cant just take out a source of data, thats not valid, u must use all the results available, its a trick question like the rest of the fucked up M/C, what a shit M/C

9 for me how fucked was that, BOS can go to hell, dickheads made a shit exam, last years was 10 times easier!

 

[GaganDeep]

lol 5 c? anyone
1.c
2.a
3b
4.c
5.c
6.a
7.a
8.b
9.b
10.b
11.d
12.a
13.d
14.c
15a

 

[angmor]

r u serias so 14 was a trick question? what the fuck that means the dumb cunts who dont know about reliability and shit are going to get the mark. what kind of a shit deal is that? FUCK THEM ALL

 

[dleroy]

6 is B i think
Glocose-Glocose-Glocose-Glocose-Glocose
5 x 180 = 900
900 - (4x18) for the four water molecules formed from the condensation reaction.
= 828

???

Your working out confuses me... i dunno how a minus sign got in there... and H20 is 17 amu, NOT 18...

 

[jfan30]

shouldnt 15 be B, you need higher temps to overcome the activation energy

 

[bboyelement]

hahha oxygen is 16 and 2 hydrogen (2.016)
thats 18 dude

 

[angmor]

wow if you are correct about that condensation thing...then fuck this was one hard MC..not hard, just fukin tricky . i thought the physics MC was tricky until this...jesus christ man

 

[bboyelement]

shouldnt 15 be B, you need higher temps to overcome the activation energy

yeh i was thinking about that ... but then i remembered from 'conquering chemistry' optimum temperature and pressure is 400 and 250 atmospheres ... so i thought 350 would be closer to 400 than 550.
dunno could be one of those trick question

 

[CheekyPunk]

yeah, this years MC was tricky.

15, the activation energy has to do with the rate of reaction, not the yield.

 

[dleroy]

shouldnt 15 be B, you need higher temps to overcome the activation energy

I dunno... when i was doing that question i visualise my textbook and i recall that the lower the temperature the better the yield..... (im not going to touch that conquering chemistry textbook ever again...! it was more like Chemistry conquering me.)

 

[alsha89]

The thing about question 6 is that when polymerisation occurs water is produced due to it being a xondensation reaction. So if 5 of the glucose monomers join then 4 water molecules will be produced also.
So if you calculate the weight of 5 glucose units = 5 * (C6H12O6) it gives you 900 but this is uncluding the water that breaks away so you must subtract the 4 water molecules = 4 * (H2O) which is 72.
So 900 - 72 = 828.

Make sense?

 

[CheekyPunk]

The synthesis of ammonia is exothermic. If you increase the temperature, its going to shift to the side which has hydrogen and nitrogen, ie less yield.
Increasing the temperature just means that it will reach equilibrium faster - with a lower yield.

 

[dleroy]

The thing about question 6 is that when polymerisation occurs water is produced due to it being a xondensation reaction. So if 5 of the glucose monomers join then 4 water molecules will be produced also.
So if you calculate the weight of 5 glucose units = 5 * (C6H12O6) it gives you 900 but this is uncluding the water that breaks away so you must subtract the 4 water molecules = 4 * (H2O) which is 72.
So 900 - 72 = 828.

Make sense?

Well if that's the case... one more mark gone... off my already 20 marks gone.... ... OMG... i hope i get at least 7 for MC... ****

 

[Sparcod]

The trickiest question is probably 5.