Questions about elements and their compounds of group 18 of the periodic table, that are generally inert and unreactive under natural conditions.

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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
44 views

Comparison of atomic radii

My teacher told me that Neon has a larger atomic radius than Fluorine.I am of the understanding that it is merely a consequence of the way we define the atomic radius and that we use Van der walls ...
6
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1answer
92 views

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 ...
10
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1answer
495 views

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 ...
8
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1answer
89 views

Why are inert gas (especially Xenon) compounds powerful oxidizing agents?

I am curious as to why compounds with inert gases, such as $\ce{XeF4}$, $\ce{XeF2}$, and $\ce{XeO3}$ are considered powerful oxidizing agents. I would attribute the phenomenon to the highly oxidized ...
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1answer
54 views

How quickly does sulfur hexafluoride mix with the atmosphere?

A common science demonstration is to float a "boat" on sulfur hexafluoride. How long would the sulfur hexafluoride stay in the container (in the experiment linked above) if the container were to be ...
4
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2answers
569 views

Solubility of Noble Gases

I read this statement that " Xenon is the most soluble noble gas in water " . My first doubt is , Why does the solubility of noble gases in water increase down the group ? Even if this is the ...
3
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2answers
1k views

Why do noble gases bond with themselves but not other elements?

Noble gases have full electron shells, which virtually blocks any other element from bonding with it. Though for some reason, noble gases can bond with the same element. For example: Helium bonds in ...
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2answers
60 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?
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Why do we use helium in balloons?

While I was looking at the periodic table today, I realised that there were gases that were much lighter than helium such as hydrogen. If hydrogen is lighter than helium, why do we insist on using ...
3
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1answer
51 views

What is the Solubility of Common Noble Gases in Concentrated Phosphoric Acid, 85% w/v?

By Henry’s Law, the concentration of a dissolving gas in a liquid is proportional to the partial pressure of that gas in contact with the liquid, mathematically, $ p = k_\mathrm{H} c$, where $p$ is ...
3
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1answer
821 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 ...
3
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1answer
126 views

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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1answer
115 views

How many argon compounds are theoretically and experimentally available?

Just as 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 known that there are some posible ...
4
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1answer
70 views

Equation Balancing Paradox

I faced this reaction which can be balanced in $2$ distinct ways which are not multiples of each other. $$\ce{6XeF4}+\ce{12H2O} \to \ce{2XeO3}+\ce{24HF}+\ce{4Xe}+\ce{3O2}$$ $$\ce{4XeF4}+\ce{8H2O} ...
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2answers
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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 ...
2
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1answer
903 views

How does the number of moles of gas affect the rate of effusion?

According to Graham's Law, the effusion rate of a gas is inversely proportional to the square root of the molar mass of the gas. However, consider this situation: We have 1 balloon with 1 mole of ...
3
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1answer
125 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 ...
6
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3answers
495 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 ...
7
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1answer
931 views

Options for long term storage of helium?

Specifically, if I wanted to purchase a large amounts of helium, what are my options for purchasing helium in a state that is suitable for long term storage? It's my understanding that if I were to ...
8
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1answer
1k views

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?
9
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What is the geometric configuration of the four fluorine atoms during the synthesis of xenon tetrafluoride?

Neil Bartlett (1932–2008) first synthesized $\ce{XeF{_4}}$ (and $\ce{XeF{_6}}$) in 1962. In the synthesis, a nickel chamber is used, and heated to 400°C, causing the formation of $\ce{NiF{_4}}$, ...