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  • There may be a slight argument about how you pronounce the name of element 117.

  • I would pronounce it "TEN-e-seen," like iodine and chlorine, but some people in America say "CHLOR-eyen" and "I-o-dyne."

  • But my feeling is that everybody will say "TEN-e-seen" because it sounds just like the state of Tennessee, whereas "TEN-e-syne" doesn't.

  • The reason why it was called tennessine is because Tennessee is the home of the Oak Ridge National Laboratory

  • where the berkelium that was used to make the element, to synthesise it,

  • the heavy target was made out of berkelium, and the berkelium sample was prepared in Oak Ridge.

  • Then, as before, we accelerate a light atom, calcium 48, a very expensive isotope of calcium, into the berkelium, and make Element 117, tennessine.

  • Now, I think that the interesting things about tennessine is to speculate about the chemistry.

  • The first thing is that you could wonder about its colour, if you could get a large lump of tennessine.

  • If you'll go down Group 17, fluorine is almost colourless, slightly green, and then as you go, to bromine is red, iodine is a dark purple colour.

  • Nobody knows what astatine looks like, and it's possible that tennessine might be a black gas, which would itself be really quite exciting.

  • Now, unfortunately the way these experiments are done is that, although you would expect tennessine being a halogen to exist as two atoms,

  • Tennessine 2 just like Cl2, you only make one atom at a time, so it's like some rare species of animal: there's just one in the zoo and you can't find a mate.

  • So we'll never know what Tennessine 2 looks like, because we can never get two atoms at the same time.

  • I would predict that Tennessine 2 would have a very weak bond, possibly the weakest bond between two atoms of the same type

  • that actually bond together, for example Helium doesn't bond to anything, but it would be a very, very weak bond.

  • The other thing which is interesting is to have a "flight of fancy."

  • Imagine what some of the compounds would be like.

  • And the one I would really like to see is "francium tennesside," a bit like sodium chloride, but with francium,

  • the element which loses an electron most easily from the alkaline metals, and tennessine.

  • And I would predict that francium tennesside would form crystals which are really quite flexible.

  • If you take caesium iodide, higher up the Periodic Table, you can bend crystals of caesium iodide without breaking them.

  • You could probably make springs out of francium tennesside,

  • but it's so radioactive that you would be got by the radioactivity long before you made the spring!

  • ...and there we have... oh, nearly two inches maybe of liquid fluorine. You can go right up that's, there's no problem with that.

  • You want to just clear a bit of the condensation off there

  • Yeah, I'm really surprised; I thought it would be pale green and it's really quite dark yellow.

  • If I'd been shown it I would have said it was liquid chlorine, but I've never seen liquid chlorine either.

  • I'm quite pleased with that. Yes.

  • I have been, as foreign secretary, giving quite a few of my notes and things to Keith to put in the archive,

  • so there will be at least some trace of me, even if you can't read my emails.

There may be a slight argument about how you pronounce the name of element 117.


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天絲氨酸 - 視頻週期表 (Tennessine - Periodic Table of Videos)

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    林宜悉 發佈於 2021 年 01 月 14 日