How Four New Elements Got Seats at the Periodic Table

4 minute read

It says something about Dmitri Mendeleev that he had an easier time keeping track of the number of protons in the nucleus of an atom than the number of brothers and sisters living under his roof. The nineteenth-century Russian chemist was the youngest of 11 siblings—unless it was 13 or 14 or maybe 16. No one ever knew, and he never clarified things for his many biographers. But then he had much bigger—and, on an elemental scale, much smaller—things on his mind.

Mendeleev was the creator of the original Periodic Table of the Elements, which he literally dreamed up one night in 1869, after falling asleep at his desk with 65 note cards arrayed in front of him—one for each element known at the time. When he awoke he had developed a way to arrange them all sensibly and systematically, from little hydrogen, with an atomic number of 1 (for its single proton) to jumbo terbium, a rare earth metal with 65 protons.

Since Mendeleev’s day, many chairs have had to be added to the table to accommodate all of the elements scientists have discovered or, more recently, created by smashing particles into each other in a particle accelerator. On Dec. 30, very big news came out of that subatomic world, when officials of the U.S.-based International Union of Pure and Applied Chemistry (IUPAC) announced that they had confirmed the existence of elements 113, 115, 117 and 118, filling out the until-now incomplete the seventh row of the table.

Elements 115, 117 and 118 were created in a particle accelerator at the Lawrence Livermore laboratory in California; number 113 popped into existence in a similar way at the Riken institute in Japan. And all of them popped out almost as quickly—lasting only a few dozen milliseconds before vanishing back into the ether. That, however, was enough — once IUPAC had reviewed all of the literature and determined that the reports from the accelerators were sound.

The new elements matter, even if their eye-blink lifespans make them a lot less relevant to us than such elemental staples as oxygen and carbon. For one thing, just because an element is not known to exist naturally doesn’t mean that it didn’t once exist—or doesn’t still, somewhere in the universe. Just as important, the ability of atoms created by collision to hold together long enough to qualify as elements reveals a lot about physics at the subatomic level. That’s important stuff for researchers trying to understand the schematics of the universe in the most detail possible.

But particle physicists are people too (albeit scarily smart ones) and discovering or creating a new element is about more than just science. It’s also about bragging rights. “To scientists, this is of greater value than an Olympic gold [atomic number 79] medal,” chemist Ryoji Noyori, the former president of Riken, told The Guardian.

With bragging rights also come naming rights. The elements currently have the placeholder names ununtrium, ununpentium, ununseptium, and ununoctium, for elements 113, 115, 117 and 118 respectively, but those will change. Like astronomers who discover new cosmic bodies, scientists who discover new elements can propose what they should be called, but with certain limitations. Elemental names have be inspired by a mythological concept, a mineral, a place, a property or a scientists—which is how we got einsteinium, fermium, mendelevium and americium (and, as long as the IUPAC is standing guard, we’ll never have, say, a trumpium or a snookium).

The Periodic Table could get bigger still. There is, in theory at least, no limit to how big an element could get, how many more places will be set at the table, or how many more physicists will thus find their names in the scientific equivalent of neon [atomic number 10] lights.

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