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  • At the time we're making this video, December 2016,

  • it is probably a unique time for the periodic table in any of your lifetimes

  • because the name of four different elements,

  • nihonium, moscovium, tennessine, and oganesson,

  • have all been announced simultaneously, and it is extremely unlikely that this will happen again,

  • four elements at once, for very long time, if ever.

  • Now, oganesson, element 118, is special for a number of different reasons.

  • The first thing which makes it very special

  • is that it is the last element on the Mendeleev

  • form of the periodic table. It completes a row.

  • The second point is that it is only the second element that has been named after living scientist.

  • [Speaking Russian]

  • and the third point is that it is a noble gas, and so will have particularly interesting properties.

  • And fourthly, and the thing which I find most interesting, is that there was a case of scientific fraud or

  • at least, scientific irregularity earlier on when a lab claimed to have discovered this element

  • and then had to retract, that is, say they were wrong.

  • So this element, oganesson, has been named in honor

  • of the very famous nuclear chemist or perhaps physicist

  • in Russia, Yuri Tsolakovich (Tsolakovich means "son of Tsolak") Oganessian

  • He is a pioneer and very long-time researcher in Dubna, the research center to the north of Moscow.

  • The only other element that was named after a living scientist was seaborguim,

  • named after Glenn T. Seaborg,

  • who was the discoverer of plutonium and several other elements.

  • There is a slight difference because oganesson

  • does not have quite the whole of Oganessian's surname in it,

  • but I think this is a trivial difference.

  • And it has often been said that having an element named after you

  • is much better than winning a Nobel Prize

  • because Nobel Prize winners get forgotten pretty quickly,

  • whereas your name is on the wall of nearly every schoolroom in the world.

  • Well, at least every science lab in the world, so it's a terrific memorial.

  • There's a bit of argument whether Einstein was told on his deathbed

  • that an element was going to be named after him,

  • but the formal naming was after his death,

  • and anyway, he didn't discover or contribute to the discovery of the element

  • so I don't think that counts.

  • I have not yet met Yuri Tsolakovich,

  • but I hope that we will meet in 2017,

  • and if we do there will be plenty of videos to mark it.

  • I think it is a terrific name, and I fully support it.

  • It is interesting because the name ends in "on," O-N,

  • which is the ending that is used for the names of all the noble gasses

  • except helium, which does end with "I-U-M."

  • The interesting thing is that as these gasses get heavier,

  • they are going to be much less volatile.

  • that is, they are going to be harder, if you like, for them to take off,

  • like it's harder for a jumbo jet to take off than for a glider.

  • If anything the evidence for element 118 is more secure

  • than for most other elements in this region of the periodic table,

  • and there is a reason why people want to be absolutely sure,

  • because in the late 1990s there was a claim from America

  • that element 118 had been synthesized.

  • You have to understand that the output from an experiment

  • is huge quantities of data from a detector, stored in a computer,

  • and then you have data analysis programs that look for the results of

  • decays of these different elements.

  • And all being well, you might discover 1 or 2 or 3 decays, but not very many.

  • What appears to have happened in this case is that one of the researchers,

  • a Bulgarian physicist called Ninov appears to have

  • in some way either changed the data or changed the algorithm

  • so it appeared that element 118 had been discovered.

  • After two or three years, it was decided that the experiments could not be duplicated.

  • Other labs tried to do it and couldn't find any trace from their particular recipe.

  • And also, even looking at the original data,

  • people couldn't reproduce the analysis, and so the original paper was withdrawn.

  • I think this is an enormously important lesson to all of you who are doing science.

  • You should enjoy the results you get,

  • and you should not try and fiddle the results,

  • or massage the data to try and make them better.

  • Because first of all, if you're found out it will destroy your reputation,

  • but most important of all, the joy of doing science is to understand nature;

  • to understand how matter behaves.

  • And if you cheat, you don't understand anything,

  • so it removes all the joy and excitement of doing science.

  • The other reason that people have got so excited about element 118,

  • oganesson, is that it completes the Mendeleev periodic table.

  • You have a nice complete row, and it looks as if it's finished.

  • And several people already asked me is there gonna be any more,

  • element 119, element 120?

  • And quite conveniently, my answer is on this Japanese tea towel,

  • where you can see, if you draw the periodic table like this,

  • it's not actually finished at 118 because

  • 119 and 120 are there on the right-hand side.

  • So... Brady -- But either way we could...

  • Even if we use the traditional Mendeleev-style one,

  • We could just start a new row, couldn't we?

  • Prof. Poliakoff -- Yes, of course we could start a new row.

  • The advantage of this format is that it shows us

  • that there's nothing special about 118 being the last one,

  • and it gives us encouragement to keep going.

  • You could, of course, say in the Mendeleev format,

  • "Well, you know, it's complete. We're never gonna be able to do it."

  • Whereas if you look here you can see it's quite reasonable.

  • I very much hope that in the next year or so,

  • that the first glimmers of a result for 119 --

  • or more probably 120, because if you look at the history of the periodic table,

  • the even elements seem to be discovered before the odd ones --

  • I think there is a real chance that we will keep going.

  • And nobody will be more excited than I am!

  • Well, perhaps Yuri Tsolakovich Oganessian may be EVEN more excited.

  • Brady - ...five years in the job! Can you imagine what that must be like?

  • Prof. Poliakoff - Yeah Brady - That's nothing, because the longest-serving

  • Foreign Secretary of the Royal Society

  • is that man behind us, a very famous scientist. This is Thomas Young.

  • Prof. Poliakoff - And my great hero, because he was such a good Foreign Secretary.

  • Brady - Now Professor, clearly I don't have to introduce you to Keith, because here's a little secret, viewers...

At the time we're making this video, December 2016,

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