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  • There's one question which, if you will skinny chemist, you can expect them to answer.

  • No.

  • And that question is, can you find flooring gas?

  • If two free in nature and they will say no, it's far too reactive.

  • As soon as Florence sees anything, it will react explosively.

  • So how can possibly you have F two gas occurring?

  • Naturally, it took hundreds of years and efforts of chemists to isolate flooring in the first place.

  • Late last night, I was reading an article in the journal Here which said, First floor in gas found in Nature, and I was amazed.

  • I really couldn't see even when I read the title how it could possibly be.

  • And it turns out to be quite an interesting effect and something that has been puzzling chemists for nearly 200 years.

  • It concerns a mineral or chemical called flow right Calcium Fluoride C.

  • A F two.

  • This is found quite widely in nature and is normally a colorless crystal.

  • You can see here, this is a lump of it.

  • There's another piece here that's broken on Dhe.

  • It looks almost like glass Know.

  • About 200 years ago, it was discovered that in one particular mind in Germany, and then subsequently in other places there was a form of flow right, which was quite darkly colored.

  • So instead of being colorless, it tender darks, purplish reddish color and when you ground this up, so I broke it up.

  • When you were mining, there was a terrible smell came out of it.

  • A Nobody knew.

  • Why is got quite an interesting name?

  • It's not called floor right when it's the smelly sort it's called and Tessa Knight, or sometimes it's called Fetid, flew right.

  • Fetid is a is a rather nasty work, meaning smelly but with really sort of quite unpleasant overtime, dead bodies, things like that.

  • So what this new papers about, and there's a press release that has come out from the From the journal.

  • There's a full paper about it is that for the first time ever, people have studied the intact crystal without crushing it up, because the problem is that as soon as you crushed the crystal and the smell gets out, you've lost it.

  • You can't analyze it and set by sniffing it through your nose if you're brave enough.

  • So what has happened?

  • Is that a lump of this material has been put in an animal machine nuclear magnetic resonance, which can detect various chemical forms of Florin, the element F and from the animal signal they worked out that in this smelly, fetid, flew right, there are tiny bubbles of Florin f too.

  • So you can all go.

  • How can you get a gas in the middle of a crystal?

  • And the answer is that this material has trace impurities off radioactive elements like uranium or thorium.

  • And when these decay and give off alfa particles or beta particles, those interact with the floor een on turn F minus into florin gas, and this gas accumulates as tiny bubbles.

  • In the solid F minus is the flowrider.

  • And in calcium fluoride, you have see a two plus on two F minus irons.

  • So what happens is you get F two on the Kelsey matter.

  • Now, of course, the calcium atom is just sitting there and a number of calcium atoms will clump together and in fact, this strange color.

  • This dark color is in fact the absorption due to the clusters of calcium atoms, and that was discovered some time ago.

  • But the question was what form was the floor rain in on Dhe.

  • Now they're sewn.

  • It's F two.

  • So although Florin is very reactive, gases very reactive.

  • It's doesn't react with calcium fluoride because that's already reacted with flooring.

  • So it's because it's made in the middle of the crystal.

  • It can exist.

  • It's a scif.

  • Something has grown inside the bottle, and therefore it cannot get out.

  • Professor, why doesn't really react with the calcium that it's split apart from?

  • Well, presumably, what happens is that they're tiny cracks or whatever in the crystal on the gas diffuses away sufficiently far that when it's trapped there, it's separated from the cluster of calcium atoms, and there's no reason why it should go back like a bubble in the spirit level, perhaps, or anything that's included a cherry in the cake like you can see up there on DDE.

  • When you grind up the rock out it comes No, The experiment has tried smelling various different gases hydrogen fluoride, various flow rides of sulfur and also Hydrofluoric acid, H f, and none of them quite smoked the same as the F two guests.

  • I'm slightly surprised because F to react with water very quickly, to form hydrogen fluoride, and since the inside of one's noted wet, I would have thought it would have reacted immediately.

  • But perhaps because smell is a very complicated sense, it doesn't rip behave in quite the same way as H F and gives you a different sensation.

  • But the important thing is that this experiment shows us that our most cherished beliefs that F two is so reactive that it could never occur in nature.

  • He's wrong on Dhe.

  • A zoo may have heard me saying on other videos, It's really important for chemistry that we keep on having our ideas challenged, that were shown that things that we believe a wrong because that will give us all sorts of new ideas that could be very useful.

  • There it is.

There's one question which, if you will skinny chemist, you can expect them to answer.

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在自然界中發現的氟氣(新聞) - 視頻週期表。 (Fluorine Gas found in nature (NEWS) - Periodic Table of Videos)

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    林宜悉 發佈於 2021 年 01 月 14 日
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