Exam Thoughts

[Milkshake]

My answers to MC
1. A
2. B
3. C
4. C
5. A (that long polypeptide with two arrows labelled X and Y)
6. D (which amino acids react with HCL)
7. C
8. C (ibuprofen lysine structural formula)
9. D (biodiesel thing split into two layers)
10. B (ratio of methane to carbon dioxide produced)
11. C
12. C (given 3 indicators and their colours, deducing the pH of solution)
13. B (gypsum being heated so that it lost 27.0g of H20)
14. D
15. A (air bag safety, 62L of gas produced)
16. B (molar mass of starch)
17. A
18. A (IR, difference b/w C-O and C-H bond)
19. D
20. B (copper sulfate in AAS)

EDIT: added few details to each q

[Greatness]

i said dilution for that question - what about the multiple choice questions about the IR spectrum and what factors influence it? i said electronegativity becuase IR doesn't work for symmetircal molecules such as O2 - what did people get?

I think it was the mass one.

[mattshen]

hey anyone know what the ratio of methane to carbon dioxide was. I got 2:3 

[Tashi]

hey anyone know what the ratio of methane to carbon dioxide was. I got 2:3 

Argh I said 1:2, my friend said she read somewhere it was 1:1. I'd like to know this?

[the.watchman]

hey yeah i got 1:2

(if anyone remembers me, im back... )

[adelaide.emily10]

i said dilution for that question - what about the multiple choice questions about the IR spectrum and what factors influence it? i said electronegativity becuase IR doesn't work for symmetircal molecules such as O2 - what did people get?

I think it was the mass one.

please explain - don't really understand why

and multiple choice q20 i thought that iii with the moving back to lower enrgy was wrong becuase atomic absorption spectroscopy is about electron absorbing energy as the move to a higher energy level and aes is about the high energy to low enegy emission so i just said a eek i think i've really fucked up this exam now !

[the.watchman]

i said dilution for that question - what about the multiple choice questions about the IR spectrum and what factors influence it? i said electronegativity becuase IR doesn't work for symmetircal molecules such as O2 - what did people get?

I think it was the mass one.

please explain - don't really understand why

i used counterexamples to eliminate the other options
electronegativity cant be, because Cl has a lower wavenumber and is less electronegative than O (C-Cl VS C-O)

[eeps]

(if anyone remembers me, im back... )

About time too.  :p

[Greatness]

i said dilution for that question - what about the multiple choice questions about the IR spectrum and what factors influence it? i said electronegativity becuase IR doesn't work for symmetircal molecules such as O2 - what did people get?

I think it was the mass one.

please explain - don't really understand why

i used counterexamples to eliminate the other options
electronegativity cant be, because Cl has a lower wavenumber and is less electronegative than O (C-Cl VS C-O)

yeah thats what i said and in my notes it says mass affects it...

[4231]

it was 2:3
a lot of people got 1:2 but that is wrong, if u go to the other post witht he exam in it and re-read the question, in reaction 2, 1 ethanoic acid is produced but in three it is doubled, so the CO2 produced in that one is 1. overall there was 6CO2:4CH4 produced

[the.watchman]

(if anyone remembers me, im back... )

About time too.  :p

lol, but not for long

i said dilution for that question - what about the multiple choice questions about the IR spectrum and what factors influence it? i said electronegativity becuase IR doesn't work for symmetircal molecules such as O2 - what did people get?

I think it was the mass one.

please explain - don't really understand why

i used counterexamples to eliminate the other options
electronegativity cant be, because Cl has a lower wavenumber and is less electronegative than O (C-Cl VS C-O)

yeah thats what i said and in my notes it says mass affects it...

i obviously dont read my notes enough

[Jdog]

the copper sulfate was D since all three occur

the CuSO4 is oxidized to Cu2+, the emission of light is caused by transition between energy levels and it does absorb red light

[mattshen]

it was 2:3
a lot of people got 1:2 but that is wrong, if u go to the other post witht he exam in it and re-read the question, in reaction 2, 1 ethanoic acid is produced but in three it is doubled, so the CO2 produced in that one is 1. overall there was 6CO2:4CH4 produced

hmmmm yea that's what i got...

[the.watchman]

My answers to MC
1. A
2. B
3. C
4. C
5. A (that long polypeptide with two arrows labelled X and Y)
6. D (which amino acids react with HCL)
7. C
8. C (ibuprofen lysine structural formula)
9. D (biodiesel thing split into two layers)
10. B (ratio of methane to carbon dioxide produced)
11. C
12. C (given 3 indicators and their colours, deducing the pH of solution)
13. B (gypsum being heated so that it lost 27.0g of H20)
14. D
15. A (air bag safety, 62L of gas produced)
16. B (molar mass of starch)
17. A
18. A (IR, difference b/w C-O and C-H bond)
19. D
20. B (copper sulfate in AAS)

EDIT: added few details to each q

sweet, i got the same as you, except for the IR one, i had B

[Water]

CuSO4 isn't oxidies to Cu2+


Cu2+   SO4 2-    , Cu2+ , same oxidation number.