All Questions
45,432
questions
13
votes
2
answers
3k
views
Why is benzyne an intermediate?
I've always seen benzyne (benzene with a triple bond) classified as an "intermediate". I really don't see why it needs to be an intermediate, though. The possible reasons I can come up with are flimsy:...
- 15.2k
12
votes
1
answer
3k
views
Living-cationic vs cationic polymerization
To my understanding, cationic polymerization is a type of living polymerization but my teacher's notes and Wikipedia seem to suggest they're different. I can't see the difference.
The same goes for ...
- 2,638
12
votes
1
answer
844
views
How is the electron "trapped in the crystal" in irradiated NaCl?
Pennsylvania State University provides irradiated $\ce{NaCl}$ (180,000 rads of gamma radiation) to teachers for a very entertaining demonstration. The salt is orange after irradiation. When it is ...
- 6,136
27
votes
2
answers
6k
views
Pros and cons of Cartesian vs. Z-matrix representations of molecules?
Over the course of my studies, I have switched largely from using Z-matrix representations of molecular geometries in calculations to Cartesian representations.
The software that I use now makes it ...
- 10.9k
13
votes
2
answers
514
views
Is aqueous medium necessary for complex formation? if so, why?
If dry ammonia gas is passed through anhydrous copper sulfate, will it turn blue (due to the formation of tetraamminecopper(II) complex)? Or will silver chloride form diamminesilver(I) complex in ...
- 141
24
votes
2
answers
89k
views
Why do different substances have different boiling points?
For example, why does for example oxygen turn into gas at a much lower temperature than water?
Does it have anything to do with the molecular structure? A water molecule does have a more complex ...
- 1,381
23
votes
3
answers
19k
views
Why is distillation not a viable way to separate ammonia from water?
Since the steam pressure of ammonia is higher than that of water, I would expect distillation to be a reasonable way of separating a mixture of both.
However, in industrial applications known to me ...
- 780
12
votes
1
answer
314
views
Are buckminsterfullerene-corannulene complexes actually stabilised by π stacking?
According to wikipedia and the references given therein, $\pi\cdots\pi$ stacking interactions are the result of interaction between the quadrupole moments of two aromatic rings, rationalising the ...
- 10.9k
22
votes
3
answers
7k
views
What makes an epoxide stable?
Overall ring strain seems to be a big issue when it comes to organic chemistry. That is why cyclopentane may be in an "envelope form" or why cyclobutane may be in a kinked, kite form. Both of these ...
- 965
35
votes
1
answer
12k
views
Why are there two Hydrogen atoms on some periodic tables?
Most periodic tables only feature one Hydrogen atom, on the top of the first group. But some, like the one I was given, also show Hydrogen in the 7th group, to left of Helium.
Why are there two ...
- 1,105
22
votes
3
answers
44k
views
Are there any major exceptions when comparing electron affinity?
I was tasked with figuring out whether carbon or nitrogen has a more negative electron affinity value. I initially picked nitrogen, just because nitrogen has a higher $Z_\mathrm{eff}$, creating a ...
- 1,105
8
votes
3
answers
6k
views
Availabilty of magnesium ions in phosphate buffer
Phosphate buffer is a common buffer in biological applications, it's especially popular for NMR. Magnesium ions are necessary for many biological systems to work, though the amount of magnesium ions ...
- 6,133
9
votes
1
answer
320
views
Why is it that the bigger the side-chain is, its hydrogen atoms tend to be more equatorial?
The most stable cyclohexane form is the chair conformation but on the other hand, the bigger the side-chain of the cyclohexane is, its hydrogen atoms become more equatorial rather than axial, which ...
- 191
29
votes
3
answers
67k
views
How do you separate enantiomers?
There are some stereochemical reactions that result in the presence of enantiomers. When moving forward with a practical organic synthesis, how does one usually separate them in order to continue with ...
- 965
99
votes
7
answers
139k
views
Why is the 2s orbital lower in energy than the 2p orbital when the electrons in 2s are usually farther from the nucleus?
My chemistry book explains that even though electrons in the $\mathrm{2p}$ orbital are closer to the nucleus on average, electrons from the $\mathrm{2s}$ orbital spend a very short time very close to ...
- 1,827