Hard questions from your field thread

>>8327561
>>8326125

code fizzbuzz

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7KB, 377x328px

>>8328409
Mass -30 peak at 137 indicates NO2 group

which means theres no acid group like the lad though but just an alcohol group and an aldehyde

then the only question remaining is, how are these attached to the aromatic ring

The multiplicity in the H nmr spectrum indicates a 1,2,3 substitution

Now just the order

For this I turn to the C NMR spectrum, and mainly the signal at 163 ppm

This is shifted too much to simply be the carbon attached to the NO2 or OH group, so I'm expecting it to be the OH group with the pi inducing effects from the NO2 group, which means the NO2 group is Meta with regards to the OH group

leading to this final structure

>>8328757
winner winner, chicken dinner

(I mean it sounds convincing)

>>8328757
Once my class gets to NMR, I won't ever need IR again, r-right?

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Let's say you find a treasure. There is a set of valuable items [math]E = (e_1, ..., e_n)[/math] and each [math]e_i \in E[/math] has both a weight (lbs) [math]w_i > 0[/math] and a value [math]v_i > 0[/math] (Both are integers).

You can only carry [math]x > 0[/math] lbs with you. Describe an algorithm that maximizes the value of the items that you can carry.

The time complexity should be at most [math]\mathcal{O}(n^2 \text{log}(n))[/math] where [math]n[/math] is the number of items.

>>8329021
Yep. We drop several grand on essentially useless IR machines just to terrorize undergrads with needlessly difficult busy work.

>>8329043
what course covers this type of problems?
and is the solution a backtracking algorithm?

>>8329021
IR is complementary to mass spec and NMR, it isn't necessary for full structural elucidation but can point you in the right direction in regards to any functional groups present. much like UV/vis

>>8329108
>needlessly difficult busy work.
literally the simplest spectra to obtain and interpret lad

>>8329164
Obviously I don't think IR analysis is difficult you fucking retard

Why do people believe String Theory is useful, when it's very obviously not?

>>8329164
That's all IRs are good at though, detecting hydroxyls or some alkene

>>8329288
it's been useful enough to inspire interesting mathematics

>>8329043
I'm sorry but this is the knapsack problem, go back to school buddeh.

>>8329288
This >>8329301, but also the fact that string theories produce classical results in addition to new expectations. People think M-theory was just pulled out of Witten's ass because they seem to believe that it ONLY makes new predictions, which is absurd. The issue is that we don't falsify part of a theory, but all of it, so we can't fully falsify all of string theory despite a lot of data supporting it.

>>8327561
I don't know anything about it but my guess is that it is supposed to form a little can with 2 flat faces and 3 side things holding it together. The 6 copper atoms are chelated by the nitrogen's lone pairs to hold it all together.

I guess it's "well defined" because other possible structures you make are probably less stable.

>>8329182
it's okay, friend. not all of us have the brain power to handle spectroscopy

>>8329021
>>8329108

i research organometallics and i have to say that >>8329164 is absolutly right. our most important means of analysis is IR, mainly because we work with carbonyl based molecules and those give beautiful bands in the IR. also for purposes of substitution with for example isocyanides we can use IR to follow the reaction and interpret the resulting product(s).

>>8327561
if 2 and 3 are primitive roots mod p where p is a prime, prove that 6 is NOT a primitive root for all such p. i doubt any of u fools can answer