I'm gonna ask you to go to your bookshelf, and take out your old chemistry textbook. If you don't have one of those somewhere, in your life, I feel sorry for you, because everyone should have at least one Chemistry textbook in their life. But assuming you do, open it up and take a look at the periodic table of elements. It's probably one the inside cover.

See that? It is no longer accurate. Totally outdated. Now, you have to go buy yourself a new $700 textbook because the periodic table of elements has just changed ... again! 

Last Wednesday, the final four elements on the seventh row of the periodic table - the ones with the atomic numbers 113, 115, 117, and 118 - were finally given names. Depending on how old your textbook is, those elements either don't have names, or aren't there at all.

But - hold up - the periodic table isn't finished yet! It took years to create these latest elements, and now scientists have their sights set on creating more new super-heavy elements in row 8, with atomic numbers 119 and above. But... no one knows how they're going to manage to do that. 

To create the four latest elements, scientists had to smash lighter elements together using huge instruments like particle accelerators. And it can take millions of collisions to create just a single atom of a new element. But the thing is, once an atomic nucleus reaches a certain size - like anything bigger than uranium, with an atomic number of 92 - the atom becomes unstable. That's because the forces that are holding all the neutrons and protons of the nucleus together aren't strong enough to hold them together over longer distances, when there are more particles.

So bigger elements are also more unstable, and they tend to decay, or break apart into other atoms with smaller nuclei, in just fractions of a second. So, in order to prove that they've created one of these new, super-heavy elements, scientists have to collect evidence of this decay. One way they do this is to record the radiation that's released as a new element breaks down.

This radiation is often released as a series of alpha particles, which are essentially helium nuclei, with 2 protons and 2 neutrons. Since each alpha particle has an atomic mass of 4, scientists can basically measure how many particles were emitted, and work backwards to figure out how big the atom was that released all of them. Plus, the bigger the nucleus, the more energy there is in each of the emitted alpha particles - which the researchers can also measure.

After all that, once there's enough evidence that a new element has been created, the element gets the stamp of approval of the International Union of Pure and Applied Chemistry - the official entity that gets to decide these things. Then the IUPAC lets the scientists who made the discovery pick a name. And the rules say that they can use any word from a myth, a mineral, a place, a property of the element, or a scientist. Kinda like Mad-Libs for chemists. 

So let's start with the first newly named element: element 113, now known as Nihonium. It's named after the Japanese word Nihon, which means "Land of the Rising Sun," a reference to the country of Japan. This discovery was the first to be made by an Asian country, and is attributed to the Japanese research center that used a particle accelerator to bombard a bunch of bismuth - with atomic number 83 - with a beam of zinc ions - with atomic number 30. 

Next up are elements 115 and 117, which were made in collaboration between labs in Dubna, Russia, and California and Tennessee in the U.S. Element 115 is now called Moscovium, to honor the city of Moscow and the team of Russian scientists that first created the element in 2003. The team smashed atoms of calcium - with atomic number 20 - into a sheet of americium - with atomic number 95 - an other labs around the world repeated their experiments over the next decade to confirm its existence. 

As for element 117, its proposed name is Tennessine for all the labs in Tennessee that worked on this and other super-heavy elements. Tennessine is the most recently discovered element, first created in 2010 by shooting calcium at another synthetic element - berkelium, with atomic number 97. 

And the last new element, 118, will be named Oganesson - to honor Yuri Oganessian,  the nuclear physicist who leads the Russian research team that helped discover several super-heavy elements, including this one. Element 118 was first synthesized around 2002, and again around 2005, by bombarding californium - with atomic number 98 - with calcium. 

So, what's next? Well, element 119 obviously. But, obviously, no one has succeeded in creating an atom that big yet! Some researchers say that creating elements past the seventh row of the periodic table is going to be tricky, because we're reaching the limit of what our particle accelerators and our measurement devices can do. We're going to have to learn how to stabilize, manipulate, and collide bigger atoms before we can figure out how big the periodic table can get. So, probably don't toss that old chemistry textbook. It's just going to need to be updated someday... probably... If we keep working hard... being cool science people. We humans have a lot more to learn.

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