Rough Solutions for Exam

[vagrantshades]

both alpha helices and beta sheets are formed from the H-bonding between -NH and -CO groups, so statement II is true

Argh this question is so stupid. Because its maintained by those functional groups, but its those specific groups that are in the peptide linkage. It can't be between any of those groups from the side chains, because that maintains tertiary structure.

[AllAboutTheLGs]

i know i dropped 2 definitely, could rise to 3-4 depending on the validity of my explanations

[jasoN-]

both alpha helices and beta sheets are formed from the H-bonding between -NH and -CO groups, so statement II is true

Argh this question is so stupid. Because its maintained by those functional groups, but its those specific groups that are in the peptide linkage. It can't be between any of those groups from the side chains, because that maintains tertiary structure.

That's quite ambiguous indeed, if they're including or excluding the side chain groups.
However I think their intention was -NH and -CO groups inside the peptide chain (because we can't assume every protein has -NH and -CO side chain groups, although most will.)

I think D is correct, but they may accept A if they recognise the ambiguity

[WhoTookMyUsername]

is mass spec a possible answer for 4d?

[illuminati]

is mass spec a possible answer for 4d?

Possibly.
The thing is tho, if your sample isn't pure and you put it through Mass Spec you could get a very similar looking mass spectrum.

i know i dropped 2 definitely, could rise to 3-4 depending on the validity of my explanations

i'd think 4 marks over 2 exams for a 50. This exam was easier than last years.

[illuminati]

also i put 0 equivalent protons

4d) i put mass spectroscopy and justified it, could that be correct?

There is debate to the meaning of "equivalent protons"
So POSSIBLY 0, don't discount it
I just can't see vcaa being so dodgy and tricking students like that
that being said it has been done before

Edit: Having re-read the question, I think they could only take 6
Because if they were equivalent protons, then you wouldn't get splitting in the first place
I think what it means is, all the protons that are adjacent to it are equivalent.

For MC i had

5) A
12) C?

different to tony chet's answers?

I don't think they'll take 5 being A tbh. 12 is C.

[Ravit]

could we use infrared spec for identification?

[WhoTookMyUsername]

I thought mass spec was a good idea when i was doing the exam,

cos no Mz peak at 17 or 18 (OH and H20 respectively)

i wrote next to it 6 non equivalent protons D:

[rocket]

I drew the graph starting at 0 instead of .06 absorbance for some stupid reason!!! I used that date to find the mg, how many marks will I lose out of the maximum four??

[WhoTookMyUsername]

can ethanol be (aq)?

would that propyl propanoate by liquid?

could you use HPLC to seperate? (cos you wouldn't want vaporised propyl propanoate!)

[charmanderp]

can ethanol be (aq)?

would that propyl propanoate by liquid?

could you use HPLC to seperate? (cos you wouldn't want vaporised propyl propanoate!)

I'm assuming you're referring to the fermentation question? That would indeed be aqueous, as the glucose itself was aqueous.

And propyl propanoate would be a liquid as it's relatively insoluble in water. Did you use liquid reactants?

[Bhootnike]

For 4d,
you could say that if you run the sample through mass spec, you can find its molecular mass, and compare that with propyl proponaotes molecular mass,
Right?

[WhoTookMyUsername]

(aq) probs? cos propanol and propanoic acid would be aqueous?

[WhoTookMyUsername]

For 4d,
you could say that if you run the sample through mass spec, you can find its molecular mass, and compare that with propyl proponaotes molecular mass,
Right?

that's what i said

[Bhootnike]

For 4d,
you could say that if you run the sample through mass spec, you can find its molecular mass, and compare that with propyl proponaotes molecular mass,
Right?

that's what i said

yeahhh bru!