noble gas compounds

[fiveworlds]

So I was watching a chemistry video about various precious metals on youtube and the man in the video mentioned that unlike what is taught in school that noble gases are known to form compounds. Does anybody here know any more about them??

[Strange]

Wikipedia has a good article. Not surprisingly, most (all?) of them are fluorine compunds.

[fiveworlds]

Yeah I had a look at it there is also various chlorides, hydrides and oxides. Such as xenon tetraoxide.

[hypervalent_iodine]

So I was watching a chemistry video about various precious metals on youtube and the man in the video mentioned that unlike what is taught in school that noble gases are known to form compounds. Does anybody here know any more about them??

A very pervasive but decidedly wrong explanation is that these atoms are able to exceed their valency because of the presence of low-lying d-orbitals. This is not in fact the case and we have known this since the 1950's or there abouts. I'm going to copy a small excerpt of something I wrote a few years back, which explains part of it.

 

The concept of hypervalency was established in the 1960s by Rundle and Musher and is defined as a compound containing a main-group element (S, P, Cl, I, etc.) whose formal valence electron count exceeds eight. Their work was based upon the then-recently devised three-center four-electron (3c-4e) bonding model, described independently in 1951 by Pimentel and Hach and Rundle as a means to rationalise the existence of compounds that appeared to violate the Lewis-Langmuir valence theory.

 

The 3c-4e model initially arose from a qualitative application of molecular orbital theory, which describes the linear combination of one p-orbital from a central atom and two ligand p-orbitals to generate three molecular orbitals (Figure 1). In contrast to localised two-electron bond (i.e. a localised σ or π bond), in which there are two molecular orbitals (the antibonding and bonding molecular orbitals; or AMO and BMO, respectively), a 3c-4e bond combines to give three molecular orbitals - a bonding molecular orbital, a non-bonding molecular orbital (NBMO; the HOMO), which contains a node at the central atom, and an antibonding orbital (the LUMO).This model has since been supported by various computational models and is currently a generally accepted archetype for hypervalent bonding.

 

 

Figure 1. Diagram illustrating the three-center four-electron bonding model, as proposed by Pimentel and Rundle. Using molecular orbital theory, three p orbitals of the two apical ligands and central atom combine to give a linear combination, with electrons fed into the nonbonding and bonding orbitals.

 

I hope that makes sense. I took out the reference numbers from the above, but I can provide them if you're interested.

Edit: this wiki article is also pretty good at explaining it. https://en.m.wikipedia.org/wiki/Hypervalent_molecule

[Sensei]

You need to have high voltage generator such as Van der Graaf generator, or Cockcroft-Walton generator,

fill tube with noble gases, and provide high voltage electrodes to it, to ionize gas.

At least.

Edited December 31, 2015 by Sensei

[Ophiolite]

So I was watching a chemistry video about various precious metals on youtube and the man in the video mentioned that unlike what is taught in school that noble gases are known to form compounds.

In the 1960s I was taught that they could form compounds, which was why they were now called the Noble gases, rather than the Inert gases.

[StringJunky]

Given the right conditions, (even if impractical) can't they be made to react with most elements? The idea being that they are inert under normal conditions of S.T.P.

[John Cuthber]

You need to have high voltage generator such as Van der Graaf generator, or Cockcroft-Walton generator,

fill tube with noble gases, and provide high voltage electrodes to it, to ionize gas.

At least.

Or you can light a candle.

 

IIRC in the particular case of xenon, you can ionise it by simply allowing it to react with platinum hexafluoride.