The heaviest (i.e. highest atomic number) readily occurring element in nature is uranium, with 92 protons. Every element above it, including plutonium, americium, and einsteinium, can only be created through processes such as fusion, or being bombarded with neutrons. Fairly large quantities of americium, for example, are produced when uranium and plutonium are bombarded by neutrons in a nuclear reactor. In the lab, most super-heavy elements are created by fusing lighter elements in a particle accelerator. Ununpentium, for example, was created by firing calcium-48 ions (a nucleus with 20 protons and 28 neutrons) at an americium target (with 95 protons and 148 neutrons), creating a fused nucleus of ununpentium-291 with 115 protons and 176 neutrons.
As
for why chemists create super-heavy elements, there are a number of
reasons. A lot of it is simply down to Russia and the US competing to
see who could discover the most exotic elements. Curiosity, of course,
also plays a big part — humans love seeing how far they can go, just for
the sake of testing the universe’s boundaries. Most importantly,
though, there is some science to be gained from such experiments. With
each new element that we discover, our knowledge of the periodic table,
and thus the universe, swells. The mere fact that we were able to
synthesize these heavy elements in the lab means there’s a good chance
that they exist elsewhere in the universe — perhaps in the supernova of a
dying star, or harnessed by an advanced alien race. Each new element also teaches us a little bit more about the island of stability — a set of as-yet-undiscovered super-heavy transuranic isotopes that are theorized to have a half-life of days or years, as opposed seconds. (The handful of unstable ununpentium isotopes created by the Swedish researchers decayed in just a few milliseconds). The theory is that, if we can cram in a certain “magic number” of protons and neutrons, these elements will suddenly become very stable. As it stands, though, we lack the technology to squeeze enough neutrons into the synthesized nucleus — and a nucleus with the wrong number of neutrons is very unstable. If we ever reach the island of stability, these stable super-heavy elements might be very useful for energy storage.
Ununpentium was originally created by Russian scientists in 2004. For an element to be officially discovered, though, a second group must replicate the work — which is what the Lund University chemists have done. Now that ununpentium has been confirmed, the IUPAC (International Union of Pure and Applied Chemistry) will meet to discuss an official name for element 115. Usually the name will be derived from something apolitical, such as a famous research or institution that is globally recognized for their work in science. Or, if IUPAC has some gamers on the board, maybe they’ll name it elerium…
Source: http://www.extremetech.com/extreme/165357-element-115-how-chemists-discovered-the-newest-member-of-the-periodic-table
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