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  • On the 10th day of christmas

  • we have two really quite unusual elements

  • which you might not have seen before.

  • We have Osmium (76)

  • which is one of the few metals that's blue

  • and this is a very beautiful crystalline example.

  • if you look (at it), it sparkles

  • as you move your head.

  • Osmium is one of the densest metals.

  • It has arguably the highest melting point.

  • There is some argument whether it's Iridium (77) or osmium. They are very close together

  • and they are both very high.

  • The other element is the hardest one to get hold of

  • of any element up to Uranium (92)

  • and this is Thorium, which is element number 90.

  • So, this was a present from Max Whitby

  • and Theo Gray

  • who are specialists in preparing samples of the elements.

  • Thorium is particularly hard to transport.

  • You can't send it through the post, because it's radioactive,

  • so they gave it to me and I brought it back to Nottingham in my pocket.

  • I was slightly worried that there might be anti-terrorist radiation-meters,

  • but I think the plastic is sufficiently thick that you can't get any radiation out from it.

  • We'll be making a video quite soon about Thorium,

  • but it's quite interresting. The sample here are more wires

  • than a lump

  • and it's a slight black-ish colour which quite surprised me.

  • The Osmium was a present from a fan.

  • I was at a conference

  • and he jumped up from the audience as I was walking through and said 'I have a present for you'

  • and whipped out some Osmium from his pocket.

  • I was amazed!

  • For day ten, we have two really exciting elements: Osmium; Thorium,

  • day nine: periodic table handkerchief,

  • a charred piece of wood,

  • seven: a fan from a fan,

  • six: element carbon,

  • five: a glowing plectrum,

  • four drinking vessels,

  • three chemical badges,

  • two periodic table bedcovers,

  • and one piece of tartaric acid from a Swiss wine barrel.

  • Let's see what we get for day eleven.

  • [Professor Mike Merrifield] ...cluster, so a pair of stars in tight orbit around one another.

  • The Sun then encounters this binary star.

  • One of the things we know about those --

  • what are called "free body encounters," so a binary star

  • has a third star coming into it -- is that the third star can

  • get kicked out at high speed. And in fact, typical speed

  • you'd expect the sun to get kicked out at in that case

  • is around 20 kilometres per second!

On the 10th day of christmas

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10: 釷和鋨(12天的聖誕節) (10: Thorium and Osmium (12 Days of Christmas))

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    林宜悉 發佈於 2021 年 01 月 14 日
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