Scientists created the first artificial elements
during World War II, and they were actually
classified at first, and it was only afterward
that they were allowed to announce the discovery
of these new elements.
When you're creating a new element, the basic
idea is that you have a target of something
and you have a beam of something else, and
you shoot the beam at the target.
Every so often, one of the beam atoms will
knock into one of the target atoms, and the
two nuclei will fuse together and you'll
geta heavy element after that fusion occurs.
So when you're deciding what atom to shoot
at another atom, in one sense, it's very easy;
it's just arithmetic.
So if you have element 100, and you shoot
element 12 at it, the resulting atom will
be an atom of element 112.
The difficulty comes in, in that, some combinations
of atoms, depending on different properties,
are very unlikely to fuse.
If you pick the wrong elements, basically
for your target and your beam, it's very unlikely
that anything will happen.
So it’s very, very difficult to tell when
they have actually created an atom of these
new elements.
And for the most part, nowadays, they are
discovering this fact retroactively, so only
after the element has already decayed radioactively
into something else.
When scientists are making these elements,
usually three or so is the rule for the number
they need to really count.
In some cases, it has taken scientists up
to nine years of work doing it, not every
single day, but doing it for months at a time.
Right now, scientists think that there could
be two reasons the periodic table could stop.
First of all, there's a very prevalent theory
that says, right around element 172,
Some weird. spooky quantum mechanical things might
happen where you're having electron-positron pairs
form and the nucleus itself might start gobbling
up electrons and destroying them,
turning them into neutrons.
But there's a lot of scientists that think
that well before the point of 172 that the
nucleus will be so unstable that it will basically
disintegrate almost instantly.
Around element 120, it's gonna be particularly
challenging to make new elements for a couple of reasons.
The first and primary reason right now is
getting enough target atoms in order to actually
produce them.
And right now, we just don't have the technology
to mass produce enough of the target atoms.
After 120, the lifetimes of these elements
also keeps dropping even more, so even if
you produce one, it gets harder and harder
to detect them at this point.
So the island of stability comes in because
there's a theory out there that says if you
have a certain magic number, as they call it, of protons
and neutrons, those nuclei will be especially stable.
And it's possible we could see exotic and
interesting traits like that emerge as we
start to get closer and closer to the island of stability.
One example of a new and exotic property emerging
unexpectedly is the element mercury.
So at room temperature, Mercury is actually
a liquid which is unlike the other elements in its column.
And because mercury is a liquid at room temperature,
it has a lot of really useful properties.
You can use it in things like thermometers, in barometers.
So a lot of early science depended
on this trait of mercury.
We have created every element up to 118.
So we have a nice complete periodic table
up to the seventh row.
The next new element that scientists create
will either be element 119 or 120.
So that'll have to go on an eighth row, by
itself, hanging out there.
Right now, scientists are content putting
these new elements in the spot they should
go on the periodic table, just based on what
their atomic number is, so based on the number
of protons that they have.
But we've already seen in a couple of cases,
a few elements that deviate a little bit,
both chemically and physically, their chemical
and physical properties from what they should be.
As we move down into much heavier atomic
numbers, we'll probably see more and more
of these anomalies.
And then it will be an actual debate--do we
put them more where they should go, or put them
more where their properties say they should go.
So scientists do think there are some good
practical reasons for trying to find these
new elements.
One is that the technologies that they're
developing to create these new elements, basically,
the particle accelerators, the separators,
the detectors things like that, can be used
in other applications.
Another application is things like radio isotopes for medicine.
A lot of the accelerators and technologies
that are used to make those nowadays were
pioneered looking for new elements.
I think it's just human nature to wanna keep
pushing, to keep going.
And the periodic table does have this really
iconic place in science where it's something
we all learn about.
We all remember it from chemistry class, even
if it's the only thing we remember.
I would bet scientists are never going
to stop making and trying to make new elements
on the periodic table.