All four are synthetic elements, meaning they are not found in nature. They were discovered by teams of scientists in Japan, Russia, and the United States, according to CNN, and are the first to be discovered since 2011 when elements 114 (Flerovium) and 116 (Livermorium) were added.
Elements 113, 115, 117 and 118 have formally been recognized by the International Union of Pure and Applied Chemistry (IUPAC). They will eventually be given official names befitting their unique properties. ABC.net.au is reporting that a spokesperson for the IUPAC said the chemistry community was happy to see the periodic table was now complete down to its seventh row.
“IUPAC has now initiated the process of formalizing names and symbols for these elements temporarily named as ununtrium, (Uut or element 113), ununpentium (Uup, element 115), ununseptium (Uus, element 117), and ununoctium (Uuo, element 118)” said Professor Jan Reedijk, President of the Inorganic Chemistry Division of IUPAC, according to a press release.
Discovery of the four elements
One of the new elements, element 113 was discovered by Japanese researchers bombarding a very thin layer of bismuth with zinc ions traveling at about 10 percent the speed of light. In theory, by doing this, the ions would fuse, forming element 113.
Kosuke Morita, the lead researcher at Japan’s RIKEN group told news media his team had worked for over seven years, looking for the data that proved element 113 existed, and only saw one event. But they refused to give up, believing one day, they would be successful.
“Now that we have conclusively demonstrated the existence of element 113, we plan to look to the uncharted territory of element 119 and beyond,” he said.
A Russian-American team at the Joint Institute for Nuclear Research in Dubna, Oak Ridge National Laboratory in Tennessee and Lawrence Livermore National Laboratory in California, discovered the other three elements. The collaborative effort by the two groups led to the discovery of the three elements initially in 2010, with subsequent confirmation in 2012 and 2013 of elements with atomic numbers Z=115 and Z=117. Work on the discovery and final confirmation of Element Z-118 began in 2006.
“A particular difficulty in establishing these new elements is that they decay into hitherto unknown isotopes of slightly lighter elements that also need to be unequivocally identified” commented JWP chair, Professor Paul J. Karol, “but in the future, we hope to improve methods that can directly measure the atomic number, Z.”
Father of the periodic table
While it is believed there were others before him, Dmitri Mendeleev is generally credited with the publication, in 1869, of the periodic table of the elements, we know today. The table was set up to illustrate trends in the properties of the then known elements and also the then-unknown properties of those elements that he expected would fill in gaps.
The first 94 elements exist in nature, although some of them are found in only trace amounts. Elements 95 through 118 have been synthesized in laboratories, but interestingly, elements 95 through 100 used to exist in nature.
The periodic table is an arrangement of the elements by order of their atomic number (the number of protons in the nucleus), their electron configurations, and recurring chemical properties. The table is usually seen as four rectangular blocks, so that within one row, or period, the elements are metals on the left-hand side, and non-metals on the right-hand side.
Surprisingly, since 1869, there have been over 700 different periodic table versions published. Besides numerous rectangular versions, there have also been a plethora of circles, cubes, cylinders, a few buildings, and spirals, as well as octagonal prisms, pyramids, and spheres, or triangles.
The following image is credited to Theodor Benfey. The elements are arranged in a spiral, with hydrogen in the center and the transition metals, lanthanides, and actinides occupying peninsulas. This table has proven to be very popular, and a good alternative to the usual periodic table seen in most textbooks.
