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  • recently a very famous British chemist, Ken Wade.

  • Can it wait of the University of Durham died on DDE.

  • He was also began his career here at the University of Nottingham.

  • He was an undergraduate here and a research student, and I found his undergraduate record card here.

  • It gives his name and so on on the front and on the back, it has his photo.

  • Andi is quite an interesting thought.

  • If you're student now watching this video that in 70 years time for 60 years time when you finish your career somebody maybe looking at your record cards and finding out what you were like when you were young.

  • Ken Wei was an inorganic chemist who spent most of his life working on the element boron on Dhe.

  • He is one of the few chemists that I know that has actually got his name into the literature.

  • There are a few people who get their names on elements.

  • Bori, um, rent again, um, and so on.

  • But that only happens after people dead.

  • Ken Wade has his name associated with the set of rules that explained the shapes of a whole series of boron compounds.

  • I can wait came up with this.

  • This theory, which is which he called apology Jewel skeletal electron pair theory.

  • But we tend to call them tens, calling my second year cycle and waits rules.

  • There's so many compounds in chemistry that it's often very confusing.

  • Why does this one have that shape?

  • When does that one have a different shape?

  • Can produce the set of rules that explained why a particular type of boron compound adopted certain shapes.

  • They allow us Thio predict the structures off these things called Waring's thes bore on hydroids compounds.

  • So this is kind of like the 1st 1 So this is this is di brains.

  • We've got these boron atoms here in black on.

  • Then we got these bridging hydride.

  • So we got two of those, okay?

  • And we've got four terminal hydrates, so it's like three.

  • If I show you, we've almost got to be a three's kind of coming together.

  • Okay.

  • On Dhe they could make bigger structures like this, which is Tetra Bori.

  • He came to this university in 1950.

  • He was an undergraduate here from 1951 to 1954.

  • So he finished as an undergraduate 60 years ago So it tells you the subjects that he studied its school.

  • It also tells you the name of his tutor who was the famous explosives lecturer Beady saw on DDE.

  • On the back is a rather fine photo of him.

  • He looked quite serious.

  • Students wore ties in those days, and over here it has his marks.

  • And over here in the final year, you can see they marked with Greek letters.

  • Alfa was good, then beaten, not so good and Gamma was terrible.

  • And here he got beater for organic chemistry, out for minus, for inorganic chemistry on for physical, he got beat.

  • A query.

  • Plus, I have no idea what that means really means.

  • I think that the stuff could put whatever number they like to this.

  • And over here it says that he did research with Dr Greenwood, and then after that, he went to the University of Durham, Andi.

  • He spent most of his career in the University of Durham, which is in the northeast of England, not far from Newcastle, where I worked early on in my career, and that's how I got to know Ken, and he was an absolutely wonderful person in terms of supporting younger researchers like me.

  • So basically what?

  • What they do is they given the shapes that they adopt.

  • So what you do is you add up.

  • You take your B eight unit on any other hydroids are left over on.

  • Do you add them up in each bait?

  • You, Nick, issue two electrons to hold your cluster together.

  • Okay, on If we have missing Verte sees that leads to open structures.

  • So we have close.

  • So if they're all closed Nikaido which means nest, I think that's like kind of slightly open than a rack.

  • Know which is more open again when it comes from Spider cobweb on DSO on.

  • The nice thing about Wade's rules is by using this other theory called isil Lobel Siri weakening to change things like ch.

  • So carbon hydrogen units for B H is and make our brains so mixed boron carbon things.

  • We can also use it for putting metals and instead so metal fragments could go in there.

  • The Taliban rings so wage rules covers a lot of a lot of areas of main group chemistry.

  • Certainly we also have his PhD thesis here.

  • You can see the title addition compounds of pro Ron, Try chloride and gallium try chloride.

  • If I can summarize his thesis rather simply boron try.

  • Chloride is a molecule with boron here and three chlorine Tze, and it's a flat molecule.

  • A plane, a molecule and it doesn't bore on does not have a CZ many electrons, as one would like for a stable compound, its so called electron deficient, so it will react with compounds like ammonia that have spare electrons.

  • So the ammonia here, with a pair of electrons shown by the silver paper, can interact with the boron to make a complex.

  • This is what he studied and you end up with a sort of complex like this.

  • We have boron here on ammonia here squeaks Well, it didn't really squeak, but you get the idea.

  • So if we look in the thesis, you can see it was last borrowed from the library in the 27th of November 1973 and it was then taken out for this video by my colleague Sam Tang on the 31st of March 2014.

  • So, as far as we can see, nobody has read this book for more than 40 years.

  • This was the kind of it's not really sad because all the important results will have Bean published in papers.

  • So this is more of the details.

  • What is interesting about this?

  • That, of course, the thesis was taken by hand.

  • There were no electric typewriters, no computers, and the diagrams were drawn by hand and actually paste it in.

  • Of course, you needed several copies of your thesis, so you had to type it with a so called piece of carbon paper like this.

  • Would you put between two seats of paper and then when you taped, if you take very hard, you could write something like four on try chloride and all being well, it will come out underneath, often not very bright.

  • This is the top copy of the thesis, which had to go into the library, and the carbon copies were given out to the supervisor and probably another copy to his parents.

  • Because most students give a thesis to their parents.

  • That's where we carbon copy ar e mails.

  • Yes, The interesting thing about Ken was that he began his career as an experimental chemist, but then later on in here his career he became more of a theoretician.

  • This type of theoretical chemistry is extremely valuable because it enables chemise doing their experiments toe understand their results.

recently a very famous British chemist, Ken Wade.

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韋德規則 - 視頻週期表 (Wade's Rules - Periodic Table of Videos)

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    林宜悉 發佈於 2021 年 01 月 14 日
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