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Xenon and the human body
Reading this article on Wikipedia: Xenon Medical applications I see that Xenon can be used as an anesthetic, neuroprotectant and doping agent.
If it is a noble gas, and thus, chemically stable, how can it have those properties?
If Xenon does not…
user435943
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How do they ensure there is one electron on an oil drop in Millikan's oil drop experiment?
Since air is ionized using X-rays, in the 'observation chamber', there must be several electrons in the chamber, so the oil drops are exposed to several electrons so it seems intuitive that a single oil drop should catch more than one electron.
Then…
Jesal Kotak
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Synthesis Golf VI: Muscarine
October's synthesis golf is rather late - apologies. I've chosen a slightly different-looking target this round, with the aim of inspiring a wider variety of routes.
Muscarine is a natural product found in some mushrooms. Most notably, it is a good…
orthocresol
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What is the smell of 'burning' metal?
When a pass a construction site where someone is welding two pieces of metal together there is a very distinct smell that I associate with 'burning' metal, although I am not quite sure it is burning in the traditional sense. Also, when someone…
Michiel
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What is K2O-nSiO2-xH2O?
In need of $\ce{K2SiO3}$ for my cucumber plants, I purchased a bag of potassium silicate. The molecular formula is $\ce{K2O-nSiO2-xH2O}$. Normally, my bags of fertilizer are easy to figure out. For example, $\ce{Ca(NO3)2}$, or calcium nitrate, has a…
Joshua E.
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In rovibrational spectra, when exactly is the Q branch forbidden?
I'm aware that the Q branch ($\Delta j = 0$) is usually not observed in rotational-vibrational spectra of diatomic molecules in the gas state, however, I've heard different things about when exactly this transition is forbidden.
I've sometimes been…
Ignacio
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What makes ABS plastic turn yellow?
If you owned old kitchen appliances or old computer you might notice that they the once cream white plastic become increasingly yellow, old and disgusting. I have read that UV lighting can damage plastics as they disrupt the structure of plastics…
nabulator
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What is behind of the attraction between a burned matchstick with a magnet?
I do not know how to understand the reasons of why a burned matchstick is attracted by a magnet (most probably) of Neodymium.
Here are some screenshots of a video in which this natural phenomenon is presented:
(In the video, see at 1 min 25…
Another.Chemist
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Why are lithides not known?
In the last few decades, many alkalides - anions of alkali metals - have been synthesised. The most famous is undoubtedly that of sodium: $\ce{[Na(\text{2.2.2-cryptand})]+Na-}$, but the alkalides $\ce{K-}$, $\ce{Rb-}$, and $\ce{Cs-}$ are all known.…
orthocresol
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What is the edge of a diamond like?
The chemical structure of a diamond is defined as an endless lattice in which each carbon atom is covalently bonded to four other carbon atoms situated at the four ends of a tetrahedron. But of course they aren't endless; diamonds have edges and…
Mason Wheeler
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Energy-efficiency aside, what are the chemical constraints on CO₂ capture and methanation?
Synthesising $\ce {CH4}$ from air and water (in a non-biological process) has been proposed as one form of energy storage. What are the chemical constraints at play here? That is to say, what sort of catalysts might be used, and what are the…
410 gone
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Structure of Br3O8
What is the structure of $\ce{Br3O8}$? It has an odd number of electrons; does that make it a free radical?
The structure given in my book shows
Where did the 7th electron of the central atom go?
Picture from book (Pg 265, NCERT Chemistry Part II,…
ghosts_in_the_code
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How can the Bonding in IF7 be explained using LCAO method?
I know that the VSEPR theory explains $\ce{IF_7}$ (iodine heptafluoride)'s structure as a pentagonal bi-pyramidal one. The valence bond theory can be used to say that it has $\mathrm{sp^3d^3}$ hybridisation (I think). How can the bonding in it be…
scienceauror
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Why are allenes chiral?
How is 1-bromo-3-chloropropa-1,2-diene ($\ce{BrHC=C=CHCl}$) chiral? It doesn't have any carbon that is connected to four different groups.
Rajath Radhakrishnan
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How to relate a reaction barrier to the time the reaction needs to proceed?
As I am writing this I am at a conference and one of the participants just asked a question where he linked reaction barriers to durations for the reaction to complete. To paraphrase:
From our experience a reaction with an activation barrier of 15…
Martin - マーチン
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