Reply With QuoteOn the whole pretty easy, nothing like "I have no clue what to do here' type questions lol. I went fairly well I reckon.
Hey guys, I did the chemistry olympiad NQE for the first time earlier this week, boy, it was challenging!
there were multiple choice in the beginning and something like 3 hard question!
So how did you guys find it?
On the whole pretty easy, nothing like "I have no clue what to do here' type questions lol. I went fairly well I reckon.
Nice, How did you go in the calculation question, it was abit annoying actually, I didn't even have time to look at the third question, it was organic or something
Cuz my friend told me to get at least 1 question right, then im garanteed a HD (he got in to the camp several times O.O)
Originally Posted by james1996mcneil
Yea lol got the calculation one, you're right though the time constraint was a stress haha, made me go much faster than I usually would. Idk what the cutoffs are for all the awards? And whats the cutoff for camp?
I seriously wish I got the opportunity to try one of those papers. Do you guys ever get your papers back when you've completed them? I'm interested in just seeing the Qs they asked this year.
Look at all the past papers lol.
I've seen the past papers. I'm just wondering though, do you guys know when (or if) exactly you get the papers for 2012 back?
I have no clue haha. My first time too. I guess it would be like ICAS comps, a few months maybe. Idk.
Did the calculation question have any trick, because i didnt see any this year and its the only question i did >.<
Last year's paper you needed to use simultaneous equation
i didnt even get time to see the other ones
How do you even do the organic one
My friend was reserve to the international team told me that most cant even get 1 question of the three, so getting 1 is will probably get you HD, getting 2 of the questions garantees you a spot in camp, and rarely if any can be able to do all 3(he did that year and was 1st!).
hey man did you get all of question 16?
i feel confident with that q except the last bit, which was some copper ion concentration
rushed through 17 and 18 =='
do you remember what you got for concentration of metal 2+ ions and nickel 2+ ions?
hmmm, i spend the test doing 16 :P don't remember the concentration exactly, it was several days ago
But i think i kinda remember the method i used to get the ion concentrations. What method did you use, like step by step wise
then i can see if you're right
17 was organic but im not rlly sure, how did you do in it
too much effort man
just found no. of moles of ETDA and multipled that by a massive number, then c=n/v
Cool, thats what i did too, how did you guys find the organic and what was the other question?(didnt even get a look at itno time)
The organic wasn't too bad once I got my head around the mass spectrometry graph (the rest of it was actually reasonably easy). I know I finished the calculation correctly (re-subbed all my final concentrations) but I'm a bit unsure of how I went in Q18 (about different bond arrangements and molecular structure) - towards the end I verged on a bit of educated guesswork rather than concrete answers; I'm not sure I'd have had any time left over within the 2hrs if I did that more judiciously.
For Q18, does the knowledge of the VSEPR theory helps in finding molecular structure(shape etc)?
Yea the mass spectrometry graph was messy
To some extent familiarity with VSEPR might have helped, but they did tell you each of the shapes in the question (for x number of bonds and y valence pair electrons, we have shapes...) so a you didn't really need it. They introduced it in all but name.
Awesome job to anyone who answered more than one of the questions. I did it last year so I can vouch that 1 question= Distinction. The people who made the camp were freaky though... is anyone doing the Biology one?
(I didnt get to do that question
So they give you all the shape and you are supposed to figure out structure/shapes of compounds they give to you right? and explain repulsion and stuff right?
Not quite. You had to determine whether molecules had net dipoles (was the total sum of the polar dipoles, considered as vectors, 0 or not - basically symmetric charge distribution or not) based on that information in the early stages.(I didnt get to do that question
So they give you all the shape and you are supposed to figure out structure/shapes of compounds they give to you right? and explain repulsion and stuff right?
Later, you were then given a series of transformations or alterations to the bond structure of certain molecules (stretching, bending certain joins, etc) and you had to decide if they would result in changes to the net dipole moment or not (would the new shape have different charge (a)symmetry?).
does anyone remember that kind of question being in a past paper? i swear i came across it before
(i mean like the stretching and transformation of molecules)
and can anyone explain what we were suppose to do for those 4 graphs concerning bromine and chlorine? in q17?
yeap im doing all three
You mean like stretchin the bond longer which effectively changes its shape right? what do you mean by bending certains bonds, do you remember an example?
Take a linear molecule (CS2, say) and bend the C=S bonds so that the S=C=S is no longer a straight line (try a boomerang, for instance). This obviously changes the net dipole on the molecule, as the charge distribution is no longer entirely symmetrical. This is trivial, but harder version of this constituted most of the last question.
AFAIK the peaks with the highest m/z are the molecule you are after, so either of the two peaks 2 amu apart at the 'end' of the graph correspond to that molecule (molecular ion, to be precise) with one of the two isotopes.
When it asks which had the same functional groups you look at the peaks for the ion fragments at lower m/z, as if the molecules had the same functional groups (Br and Cl can just be 'swapped' out in the molecule) we would expect them to form similar patterns once fragmented to a degree.
Last edited by alexandred; 14 Aug 2012 at 8:03 PM. Reason: Spelling failure
yea i looked for peaks which were 2amu apart, but i swear the absolute highest peak was always in the middle?
am i getting something wrong?
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