Xenon oxide photochemical preparation?

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Discussion Overview

The discussion revolves around the photochemical preparation of xenon oxides, particularly focusing on the potential direct reaction between xenon and oxygen, as well as the implications for xenon lamps. Participants explore historical references, experimental observations, and theoretical considerations regarding the stability and reactivity of xenon oxides.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant recalls a presentation about xenon and oxygen forming crystals under sunlight, but later questions the accuracy of this memory.
  • Another participant notes that xenon does not react directly with oxygen, suggesting that xenon oxides are typically produced by reacting xenon fluorides with oxygen.
  • A participant raises concerns about the explosive nature of xenon oxides, particularly in the context of high-pressure xenon lamps, speculating on the potential for unstable oxides to form in microcracks of the lamp's quartz envelope.
  • One participant proposes that ozone, formed from oxygen exposed to UV light, could react with xenon, potentially leading to the formation of explosive xenon oxides like XeO3 or XeO4.
  • Another participant expresses uncertainty about their understanding of xenon chemistry, framing their reasoning as a hypothesis rather than a definitive claim.

Areas of Agreement / Disagreement

Participants express differing views on the reactivity of xenon with oxygen, with some adhering to established knowledge while others propose alternative scenarios. The discussion remains unresolved regarding the direct reaction between xenon and oxygen and the implications for xenon lamps.

Contextual Notes

There are limitations in the discussion, including potential misremembering of historical experiments, the dependence on definitions of reactivity, and unresolved questions about the mechanisms of reactions involving xenon and oxygen.

JohnRC
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In 1994 I attended a symposium at University College London to celebrate the centenary of William Ramsay's discovery of argon. In a rather remarkable presentation there some slides were shown of some beautiful clear large crystals in a sealed quartz flask.

If my memory is not playing tricks on me, I think the lecturer said something even more surprising: that the crystals were the result of leaving an equimolar mixture of xenon and oxygen in the flask to be irradiated in strong sunlight in the middle of a sports field. After the photographs were taken the flask was destroyed by throwing stones at it, because the product, an oxide of xenon, was too unstable and explosive to be safely handled in the flask.

It is a long shot, but has anyone else a lead on this experiment? A publication? A similar lecture? Some detail that I might have got wrong? I have failed to find anything like it, but would rather like to have a reference.
 
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Apologies to all. I think I must have misremembered -- have discovered that xenon difluoride can be prepared in an exactly analogous way to what I have described with a mixture of xenon and fluorine gases.

Will leave this thread open just in case anyone does have information about a direct reaction between xenon and oxygen.
 
I had read that Xenon do not react directly with Oxygen. Instead, Oxides of Xenon are obtained by reacting fluorides of Xenon with Oxygen.
 
AGNuke said:
I had read that Xenon do not react directly with Oxygen. Instead, Oxides of Xenon are obtained by reacting fluorides of Xenon with Oxygen.

Yes AGNuke, that is certainly the received textbook wisdom.

I did have a purpose in asking specifically about the direct reaction. For many years I have wondered why high pressure xenon lamps occasionally explode with a violence that seems extreme, even allowing for a high working temperature and high internal pressure in the quartz envelope. These lamps are often used as continuous sources of intense UV radiation in photochemical studies.

Was wondering about the possibility of buildup of unstable explosive xenon oxides where the two gases could come into contact in microcracks in a quartz envelope.
 
Here's what I think of your assertion. According to another divine textbook wisdom, Xenon Short Arc Lamps has high spectral emission in Ultra-Violet region. And it doesn't require explanation what happens to O2 when it is exposed to UV.

Now, if the oxygen diffuses inside the quartz envelope due to some defects or something like that, Ozone will come in direct contact with the Xenon Gas. Correct me here, but I think that Ozone is one of the strongest oxidizing agents, just falling short of Fluorine, which can oxidize Xenon on its own, so why not Ozone?

Then what, for a moment, XeO3 or XeO4 can be formed, both of which are very explosive even at room temperature, let alone at the temperature attained in the Xenon Lamps. Then no need to tell what will happen.

This is the best reasoning I can come up with. I don't know anything about Xenon chemistry. In fact, I only learned 12th grade chemistry in my country, so I don't know whether my "hypothesis" stands or not.