ATAR Notes: Forum

Archived Discussion => 2010 => Mid-year exams => Exam Discussion => Victoria => Chemistry => Topic started by: stonecold on June 09, 2010, 02:21:49 pm

Title: MC ANSWERS
Post by: stonecold on June 09, 2010, 02:21:49 pm
This is what I got.  Not saying it's right, just for comaparison.  Let me know if you have something different or I'm wrong and I shall change it.

1. C
2. D
3. A
4. C
5. C
6. A
7. A
8. B
9. B
10. C
11. A
12. D
13. B
14. D
15. B
16. C
17. D
18. B
19. C
20. B
Title: Re: MC ANSWERS
Post by: qshyrn on June 09, 2010, 02:25:38 pm
same, except i got c for 4 and d for 5   (what were these questions again?
Title: Re: MC ANSWERS
Post by: 10weid on June 09, 2010, 02:26:06 pm
C
D
A
C
C
A
A
B
B
C
A
D
B
D
B
C
D
B
C
B
Title: Re: MC ANSWERS
Post by: Studyinghard on June 09, 2010, 02:26:11 pm
I only remember the first 5. Did anyone else think the first MC that all were wrong answers.

Not sure but was question 4 answer 2/7 mol? thats what I got.

and 5 was like 249L?
Title: Re: MC ANSWERS
Post by: stonecold on June 09, 2010, 02:27:06 pm
nah, it was 5/7 mol, wasn't it in excess?
Title: Re: MC ANSWERS
Post by: matty.k on June 09, 2010, 02:27:33 pm
i also got C for 4 5
Title: Re: MC ANSWERS
Post by: stonecold on June 09, 2010, 02:28:08 pm
4 and 5 five are C c sorry, i mustve copied out wrong in a rush, becasue I got 249 L :)
Title: Re: MC ANSWERS
Post by: Studyinghard on June 09, 2010, 02:28:28 pm
nah, it was 5/7 mol, wasn't it in excess?

yeah but when your doing ratios you dont take the difference in the mole. you do from the equation. which was 2/7

matty.k i got some answers for those questions as you.
Title: Re: MC ANSWERS
Post by: 10weid on June 09, 2010, 02:28:51 pm
yeah, 2/7 mol reacts, maening 5/7 mol is in excess, which was option C....
Title: Re: MC ANSWERS
Post by: Studyinghard on June 09, 2010, 02:29:44 pm
Was 12 option D the one where which would react with dilute HCL and NaOH ? I put it the acid which was option C for the whole exam then with 2 mins left I changed it to the amino acid.

is 12 D for sure?
Title: Re: MC ANSWERS
Post by: 10weid on June 09, 2010, 02:32:39 pm
it was d, as an amino acid may act as an acod pr a abse, which is the answer rewquired
Title: Re: MC ANSWERS
Post by: Studyinghard on June 09, 2010, 02:33:41 pm
phewww.

OO what did people do for the question about the concentration of oxalic acid. I did 0.750M
Title: Re: MC ANSWERS
Post by: 10weid on June 09, 2010, 02:40:51 pm
yeah, im farily certain it was .75, as the acid was clearly diprotic, meaning thta f the reacitonn goes to completion it gives away both protons, reuqiring 2 mol of NaOH
Title: Re: MC ANSWERS
Post by: Studyinghard on June 09, 2010, 02:41:58 pm
winnnn...i changed that at the last second too XD
Title: Re: MC ANSWERS
Post by: kyzoo on June 09, 2010, 02:43:57 pm
Hmm...apparently with the insulin one the number of peptide links is 49 because insulin is made of 2 strands??? Can someone confirm this? Did the question actually say insulin was made of 2 strands because I don't remember seeing that.
Title: Re: MC ANSWERS
Post by: tram on June 09, 2010, 02:44:40 pm
This is what I got.  Not saying it's right, just for comaparison.  Let me know if you have something different or I'm wrong and I shall change it.

1. C
2. D
3. A
4. C
5. C
6. A
7. A
8. B
9. B
10. C
11. A
12. D
13. B
14. D
15. B
16. C
17. D
18. B
19. C
20. B

same except:

2:B
15:C

I think i was wrong for two, i know other ppl also got D, anyone know the question?
Title: Re: MC ANSWERS
Post by: Studyinghard on June 09, 2010, 02:45:56 pm
This is what I got.  Not saying it's right, just for comaparison.  Let me know if you have something different or I'm wrong and I shall change it.

1. C
2. D
3. A
4. C
5. C
6. A
7. A
8. B
9. B
10. C
11. A
12. D
13. B
14. D
15. B
16. C
17. D
18. B
19. C
20. B

same except:

2:B
15:C

I think i was wrong for two, i know other ppl also got D, anyone know the question?

Which indicator which was definitely D Bromophenol Blue
Title: Re: MC ANSWERS
Post by: 10weid on June 09, 2010, 02:47:30 pm
yepp!
umm 15 i got also got B, which was that question?
Title: Re: MC ANSWERS
Post by: kenhung123 on June 09, 2010, 02:48:00 pm
I think it was thymol blue because it should change colour after equivalence point
Title: Re: MC ANSWERS
Post by: Studyinghard on June 09, 2010, 02:48:07 pm
was 15 the amino acid insulin question. fkn it was 49 and not 50! i got trickeddddddddd big time.
Title: Re: MC ANSWERS
Post by: crayolé on June 09, 2010, 02:48:45 pm
FARRR
I got the right answer for 1, i circled the wrong box :@

^^^How was it 49? :/^^^
Title: Re: MC ANSWERS
Post by: kenhung123 on June 09, 2010, 02:49:49 pm
Hmm...apparently with the insulin one the number of peptide links is 49 because insulin is made of 2 strands??? Can someone confirm this? Did the question actually say insulin was made of 2 strands because I don't remember seeing that.
Hmm it said 1 molecule of insulin...and it said how many peptide in 1 molecule and 1 molecule had 51 amino acids
Title: Re: MC ANSWERS
Post by: 10weid on June 09, 2010, 02:51:47 pm
one molecule contains trwo polypeptide chains
meaning that there are 51-2 peptide links = 49 peptide links :)
Title: Re: MC ANSWERS
Post by: Studyinghard on June 09, 2010, 02:52:08 pm
I KNOW WTF IT SAID ONE MOLECULE. and people are saying 2 strands? was there 2 strands in the question? If so then 49 is right but i remember seeing 1 strand. :S
Title: Re: MC ANSWERS
Post by: 10weid on June 09, 2010, 02:52:45 pm
two stanrds, connected by disulfide bridges..
Title: Re: MC ANSWERS
Post by: tram on June 09, 2010, 03:02:20 pm
Hmm...apparently with the insulin one the number of peptide links is 49 because insulin is made of 2 strands??? Can someone confirm this? Did the question actually say insulin was made of 2 strands because I don't remember seeing that.
Hmm it said 1 molecule of insulin...and it said how many peptide in 1 molecule and 1 molecule had 51 amino acids

i defs don't remeber seeing two strands.........
Title: Re: MC ANSWERS
Post by: Studyinghard on June 09, 2010, 03:09:45 pm
There are 2 strands. FCK!

can someone confirm if 4 MC is C?

If MC 4 is C then I got 18/20.
Title: Re: MC ANSWERS
Post by: 10weid on June 09, 2010, 03:14:04 pm
yeh it's c
Title: Re: MC ANSWERS
Post by: Benny1234 on June 09, 2010, 03:17:00 pm
the question did say there were two strands. Each strand would have one less peptide link than amino acid so its 51 minus 2 = 49
Title: Re: MC ANSWERS
Post by: Russ on June 09, 2010, 03:17:31 pm
one molecule contains trwo polypeptide chains
meaning that there are 51-2 peptide links = 49 peptide links :)

Yeah, it's a subtle distinction.
Title: Re: MC ANSWERS
Post by: kenhung123 on June 09, 2010, 03:26:32 pm
Far out I thought 1 molecule=1chain
Title: Re: MC ANSWERS
Post by: Blakhitman on June 09, 2010, 03:39:14 pm
Woot I got 49 toooo. Defintely two strands.
Title: Re: MC ANSWERS
Post by: Greggler on June 09, 2010, 03:42:01 pm
devo got 15/20. I knew MC were going to let me down. But SA was easy so hopefully can still end up with high 60's out of 75
Title: Re: MC ANSWERS
Post by: Blakhitman on June 09, 2010, 03:58:46 pm
What was the last question?

was it the polymer one? if so I know I guessed that becuase I just can't do that.

arrrgh 17/20 for me if those are all correct. I put D for both 4 and 5, what were the questions again?
Title: Re: MC ANSWERS
Post by: Russ on June 09, 2010, 04:03:59 pm
What was the last question?

was it the polymer one? if so I know I guessed that becuase I just can't do that.

arrrgh 17/20 for me if those are all correct. I put D for both 4 and 5, what were the questions again?

Yes, q20 for the MC was the polymer one.

Question 4 was the mole ratio question (i agree with C) and question 5 was the TNT one (i agree with C)
Title: Re: MC ANSWERS
Post by: vexx on June 09, 2010, 04:04:02 pm
awesomeee i hope these answers are correct 20/20 :D
Title: Re: MC ANSWERS
Post by: tram on June 09, 2010, 04:06:08 pm
dammit.....looks like i'm on 18/20.....and the sa's aren't looking too gud :(
Title: Re: MC ANSWERS
Post by: slothpomba on June 09, 2010, 04:06:13 pm
Anyone else get like a smaller number of D's compared to the rest of the letters or was that just me
Title: Re: MC ANSWERS
Post by: qshyrn on June 09, 2010, 04:13:29 pm
can someone explain why no.5 is C???   i converted the Tnt to volume then worked out the volume s of the others then added those together.. got 275 (D)
Title: Re: MC ANSWERS
Post by: superflya on June 09, 2010, 04:14:44 pm
u added the the volume of the solid, i did that too but then changed it :P
Title: Re: MC ANSWERS
Post by: Blakhitman on June 09, 2010, 04:15:23 pm
That's what I got aswell...I think it was 274

aargh superflya...bleh.
Title: Re: MC ANSWERS
Post by: Studyinghard on June 09, 2010, 04:16:48 pm
V of CO2 = (6 * 8.31 * 300)/100 = 150
V of H2   = (2.5 * 8.31 * 300)/100 = 62
V of N2 = (1.5 * 8.31 * 300)/100 = 37

37 +62 +150 = 249
Title: Re: MC ANSWERS
Post by: Blakhitman on June 09, 2010, 04:19:10 pm
Can't believe they had a solid there, that's worse than the amino acid one because that clearly said 2 strands...why couldn't they have said a solid is formed aswell!!!!!!!! fml...
Title: Re: MC ANSWERS
Post by: qshyrn on June 09, 2010, 04:22:38 pm
u added the the volume of the solid, i did that too but then changed it :P
lol  IN THE EXAM I MADE A MENTAL NOTE NOT TO ADD THE VOLUME OF THE SOLID  looks like that didnt help much
Title: Re: MC ANSWERS
Post by: supernatural on June 09, 2010, 04:47:49 pm
im pretty sure question 15 was C
Title: Re: MC ANSWERS
Post by: Studyinghard on June 09, 2010, 04:49:17 pm
im pretty sure question 15 was C

nope definitely B.

2 separate strands. total 51 amino acids.
1 strand has 26 AA and 1 strand has 25.

peptide linkages = Amino acids - 1
26 - 1 = 25
25 - 1 = 24
= 49

Dw i made the same mistake.
Title: Re: MC ANSWERS
Post by: kenhung123 on June 09, 2010, 04:53:07 pm
For the volume question, I just found volume of the reactant and I remember the closest answer was like 2 L below...coz the volume shouldn't change i think?
Title: Re: MC ANSWERS
Post by: appianway on June 09, 2010, 06:10:22 pm
It was definitely two strands. I remember underlining it...
Title: Re: MC ANSWERS
Post by: taiga on June 09, 2010, 06:10:54 pm
Lmao I put 49 but didn't even think of that strands stuff.