Questions tagged [noble-gases]

Questions about elements of group 18 (group 0 in old notation) of the periodic table and their compounds, created despite the low reactivity of these elements.

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23
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3answers
10k views

Why are noble gases stable

I was recently asked the question "Why are noble gases stable? with the expectation of providing an answer beyond the general explanation of "they have full valence layers" and I couldn't think of one....
19
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1answer
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Why can't helium be solidified at 'ordinary' pressures?

According to the UC Davis ChemWiki Chemistry of Helium, helium has a comparatively unusual property, specifically: Helium is the only element that cannot be solidified by lowering the temperature ...
28
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1answer
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What is the molecular structure of xenon hexafluoride?

Xenon hexafluoride, $\ce{XeF6}$, can be obtained by reaction of xenon with excess fluorine gas. What is the gas-phase structure of the molecule? What experimental evidence is there to support it, ...
3
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2answers
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Structure of xenon hexafluoride

The central atom has a hybridization of $\mathrm{sp^3d^3}$. Thus, its structure should be pentagonal bipyramidal. Why is it not that but a distorted octahedron?
13
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1answer
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Do noble gasses besides Helium form diatomic molecules at low temperatures?

I know that at extremely low temperatures (mK and lower), Helium can form diatomic molecules. Do the other noble gasses also form molecules at extremely low temperatures?
12
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2answers
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How do noble gases bond with themselves?

Noble gases have full electron shells, which virtually blocks any other element from bonding with it. However, I've heard about cases where they bond to each other - for example, helium can ...
9
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1answer
20k views

Electronegativity in krypton and xenon?

Why do krypton and xenon have high electronegativity? Noble gases are supposed to be "happy" with the amount of electrons they have, because they have 8 valence electrons (thus, most noble gases have ...
16
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4answers
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Why do the melting and boiling points of the noble gases increase when the atomic number increases?

What causes the melting and boiling points of noble gases to rise when the atomic number increases? What role do the valence electrons play in this?
21
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2answers
7k views

Why do XeO and XeF8 not exist?

Since Neil Bartlett's 1962 discovery that xenon was capable of forming chemical compounds, a large number of xenon compounds have been discovered and described. Almost all known xenon compounds ...
20
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2answers
3k views

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 ...
13
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1answer
210 views

What is the geometric configuration of the four fluorine atoms during the synthesis of xenon tetrafluoride?

Neil Bartlett (1932–2008) first synthesized $\ce{XeF4}$ (and $\ce{XeF6}$) in 1962. In the synthesis, a nickel chamber is used, and heated to 400°C, causing the formation of $\ce{NiF4}$, which ...
10
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1answer
647 views

Stable natural helium hydride?

Reading the transcript of the Royal Society of Chemistry podcast Helium Hydride, they state that helium hydride is possibly the most ancient compound to form in the Universe. They make the assertion ...
3
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1answer
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Are ther known compounds of Argon? What is their molecular geometry and hybridisation?

Can Argon hybridize orbitals and/or form covalent-like/ionic-like compounds? Is there any study of that? I would be happy to read concrete references. What kind of molecular geometries for argon ...
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2answers
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How can an excited helium dimer be formed?

Why does a collision between an excited helium molecule ($\ce{He^*}$) and a ground-state helium atom create $\ce{He2^*}$?
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2answers
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Can you in reality give neon a charge of +8?

First off, I am currently confused about why neon can even be ionized at all. But since it can be ionized, this is the energy required to give a mole of neon a charge of +8: ...
8
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1answer
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Why are there more fluoride compounds formed with Xenon?

Based on WebElements, of the Noble Gases, $\ce{He}$ and $\ce{Ne}$ do not react with any of the halogens; however: $\ce{HArF}$ has been detected at low temperatures (thank you to @bon and @Martin in ...
5
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1answer
140 views

Compound with a bright green emission when electrically excited

I rolled back the edit because I really am looking for the following: I am looking for an element or compound that would have a bright green emission when electrically excited and is a gas at between ...
5
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1answer
291 views

Which argon compounds exist, supported by experiment or computation?

Just as $\ce{HArF}$ was synthesized...Could something like $\ce{Li-Ar-Li}$ exist with AXE geometry $\ce{AX2E3}$? Any other argon compound proposals out there? I also know that there are some posible ...
4
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1answer
6k views

What is meant by complete outer shell? Why do the noble gases have zero valency?

Does having 8 or 2 electron in the outmost shell mean its outmost shell is full and its valency is zero? I know that the 3rd and 4th shell can contain 18 and 32 electrons. Then how can Argon's (2,8,...
3
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1answer
211 views

Are there natural conditions that could enable the formation of noble gas compounds?

Noble gases were considered to be inert until compounds that include them, such as xenon trioxide (as an example) were found. My question is, what natural conditions allow the formation of noble gas ...
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1answer
2k views

London Forces and Liquifying Noble Gases

From my book, it says that 'without van der Waals (London Dispersion) forces, it would be impossible to liquefy noble gases.' Why is this the case?
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2answers
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Why can't helium nuclei (alpha particles) react with fluorine?

Alpha particles are basically just helium nuclei, so it will accept an electron pair to become stable. Will fluorine, being highly electronegative, not just donate an electron pair but form a bond ...
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2answers
180 views

Electron affinity

Concerning the liberation of energy when an atom that is close to the configuration of a noble gas: Where does the energy dissipated from an atom upon receiving an electron come from?