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So it has been quite an exciting time for the elements
recently. We had element 112 that got its name
copernecium…oops hang on, we must stop, I have got the
wrong tie.
So it has been an exciting couple of months for elements we
had element 112 named copernecium and now yesterday or
just the end of last week, it was announced that the synthesis
of, element 114, had been repeated. It was made about 10
years ago in a place called Dubna in Russia, rather to the
north of Moscow, it was made like the other super heavy
elements, by fusing two nuclei, two atoms together. So in
this case they took an atom of plutonium which has atomic
number 94, so to get to 114 you need to add 20 to 94, so
they used atoms of calcium which has atomic number 20 and
electrically-charged atoms of calcium were accelerated to
huge speed and banged into targets of plutonium. Now the
people who did the new work which was in Berkeley in
California had their machine running for 8 days banging away
the calcium atoms into a target of plutonium oxide and
managed to observe two atoms of element 114. Just think for
a moment, the tiniest grain of dust that you can see, like the
dust you see on this table, will have hundreds of thousands of
millions of atoms in it. So if you have one or two atoms you
can, not only can you not see it but you can’t tell anything
about the properties of the elements or whatever.
Now the reason people were trying to make element 114 is
because there have been long standing predictions, by people
who do the theory, that perhaps element 114 might be much
more stable than the other elements that have heavier than
uranium. They imagined, or suggested, that there would be
an island of stability, so you would go through a lot of
elements, 110, 111, 112 that would be very unstable and
then suddenly you would get to 114 which would be much
more stable. Unfortunately, it turns out from the experiments
that it is not the case. They are only stable for a fraction of a
second and, like the other heavy elements, they decay from a
whole series of different elements, which themselves can be
detected. So you can see here the decay chain of element 112
here and borium and a whole series of them and soon there
will be another decay chain for element 114. Now the real
importance of this experiment is that the original work in
Russia has been repeated somewhere else. Now nobody
doubted that the Russian experiment was correct but it is a
general principle of science that nobody believes an
experiment completely until it has been repeated. When my
students do an experiment and get a good result, I
congratulate them and then I tell them to do it again just to
make sure that it works. But of course, just because the
same person does the same thing twice they might be
making the same mistake without realising it. So if somebody
else using completely different equipment, in a completely
different lab does the same experiment and gets the same
result then everybody will believe it, and so this is really quite
an exciting event because now element 114 has been really
quite well established and presumably soon people will be
choosing a name and it would be very interesting to see what
they choose and at this stage I am not quite sure what they
might choose but I hope they will be inspired by the German
team that named element 112, and name it after somebody
who is neither Russian nor American but who is a famous
scientist who’s inspired others.