Questions about noble gas

[JMBuilder]

1. After being ionized, does noble gas restabilize itself? If so, how long does it take?

2. It's fairly easy to bombard noble gas with photons and strip the electrons off, giving it a positive charge. Is it possible to add an electron, giving it a negative charge?

[Kryten]

1. Depends entirely on what else is around and what temperatures it's at. Within a few seconds at most if not kept at plasma-forming temps.

2. Only in a few extreme cases, with a few noble gases (the heavier ones), and the result is extremely unstable

[JMBuilder]

1. What about in the vacuum of space?

2. While it had a negative charge, and you fused it with hydrogen, what would happen when you stopped charging it?

[Kryten]

In the vacuum of space the gases' own removed electrons would logically still be around to recombine, in most cases. If not, well, it's going to stay that essentially forever.

And, uh, actually I was wrong on the second one. I can't find any actual chemicals which involve noble gases in negative oxidiation states, only ones where they've been oxididised themselves (e.g. flourine compounds.). It looks like they can't be negatively charged under practical conditions.

[nyrath]

An ion flying out of the exhaust of an ion drive into the vacuum of space is not going to find any electrons to unionize themselves. This means that the spacecraft will become more and more negatively charged. Eventually it will be so charged that the ion exhaust will be bent around until it strikes the ship and/or the ion accelerator cannot counteract the attraction of the ship so they refuse to leave the ion drive exhaust port.

This is why ion drives have cathodes emitting electrons. This neutralizes the beam and prevents the ship from becoming charged.

[bivouac]

1. After being ionized, does noble gas restabilize itself? If so, how long does it take?

Depends upon the gas and its surroundings. In atmospheric conditions, nanoseconds if not femtoseconds. If literally anything come into contact with it, the noble gas cation will oxidize whatever it touches. (Though probably not another atom of the same species.)

2. It's fairly easy to bombard noble gas with photons and strip the electrons off, giving it a positive charge. Is it possible to add an electron, giving it a negative charge?

It would be worthwhile to not that it's not fairly easy to strip an electron off of a noble gas. Quite the opposite actually. While the methodology may seem simple, the actual process requires quite a bit of energy. In terms of kJ/mol (kilojoules per mole), thermite releases about 850 kJ/mol. Removing an electron from Neon requires about 2000 kJ/mol. Helium and neon for no known stable compounds. They retain their electrons to a rather extreme extent. I've seen He+ and He2+ tossed around in coursework examples, but those are strictly for number crunching. In so many words, it just doesn't happen. Argon compounds have been observed under extremely controlled conditions, but they do not occur naturally (that we know of anyway). It would also be worthwhile to note that virtually every case of a noble gas forming something almost always involves fluorine. Fluorine very aggressively strips electrons from other elements/compounds/whatever-is-around-it. (Please note as well that I'm talking about fluorine and NOT fluoride. One obliterates and the other fights cavities.) It's a pretty weird and unique element, allowing it to bond with other elements that would typically never bond with anything else. Why mention the bonding? Things like fluorine reduce the amount of external energy input required to strip an electron. If we're going to do it using a photons, we'll need to create the same extreme conditions using just light. The energy requirements are a bit... intense.

Think of this stuff like a complimentary system. When we put energy in, the additional energy needs to translate either into the system or to its surroundings. When we remove an electron from a system, if it has nothing from which to gain the electron lost, it's kind of on its own in a quasi-stable state. However, if we add an electron, the system can readily eject that electron if there's too much energy in the system. The positive charge exerted by the nucleus would be unable to successfully hold onto the introduced electron. With such a weak grip, the electron will be lost. All of these elements want to stay in the most stable state possible relative to their surroundings. Remove an electron, and it'll hold onto the others more tightly. Add an electron, and it'll interact with the other electrons (causing the electron cloud to expand) and nucleus from its own separate orbital. (Look up s, p, d, and f orbitals. It'll either confuse you more or help you understand better.) Generally, all atoms want some sense of a completed orbital shell. If we have just one electron in its own orbital, the system would become more stable if it got rid of the additional electron. In something like a noble gas, the amount of energy from intermolecular forces and repulsion would exceed the energy required to retain the electron. Thus, it gets ejected from out system. Similarly, this is why things in the first group in the periodic table form cations. There's a lone electron in its own orbital.

If you look in a reference table such as the CRC Handbook of Chemistry and Physics, there are actual values for all of this and so much more. Is it possible? Absolutely! Is it practically feasible? Sweet Jesus no! HOWEVER! When we start getting into the heavier elements, the sheer mass and charge of the native element may be able to retain an additional electron. Given a huge charge and a whole lot of electrons, the impact from a single additional electron would be substantially less than if we added an electron to a lighter element. The same goes for removing an electron as well. This is why Xenon is kind of an ideal candidate for such things. Radon would be an even better candidate, but it makes the Geiger counter go tickety-tick-tick. Also, there's less of it.

Eh. I'm only partially satisfied with this explanation. Let me know if you want more elaboration/clarification.