In the periodic table, it is also the periodic table, added four new member. These numbers are 113, 115, 117 and 118, and completely cover the seventh row in the table. Discoverer of 115, 117 and 118 of the elements recognized by the team of Russian and American scientists from the Joint Institute for Nuclear Research in Dubna and Lawrence Livermore National Laboratory in California, and the opening of the 113th reserved for researchers from Japan.
All the newly introduced superheavy elements are radioactive and, for the first time they were discovered a few years ago, but double-check the information on the time spent. This is the first change in the periodic system since 2011. Here’s what you need to know about this scientific discovery.
What are their names?
So far, 113, 115, 117 and 118 members have a working title and three-letter designations in accordance with the serial numbers: Uut (ununtrium), Uup (Ununpentium), Uus (Ununseptium) and Uuo (ununoctium). The right to come up with elements of permanent names and symbols belong to their discoverers, then names will adopt the International Union of Pure and Applied Chemistry (IUPAC).
None of the new elements not found in nature
Each of the elements in the periodic system is the atomic number, which corresponds to the number of protons in the atomic nucleus. In new elements 113, 115, 117 and 118 of protons; because the protons repel each other, the atoms with such a large number of them are too unstable to be found in the “wild” nature. The heaviest of the existing natural environment elements is uranium (atomic number 92), heavier elements are synthesized artificially and there is a very short time (of a second), and then break down into simpler elements.
How to get new items ?
Simply put, the elements of high atomic number are synthesized from other, more easily. To get Ununseptium (117), the researchers bombarded the nucleus of berkelium (97 protons) isotopes of calcium-48 (20 protons). As reported Scientific American, only one experiment to create a sufficient number of Berkeley, which itself is a rare element, – 13 mg – took two years. For synthesis Ununpentium (115) using the calcium and americium (95) for ununoctium (118) – Calcium and CA (98) and ununtrium (113) can be prepared by the decay of the isotopes Ununpentium and similar reactions neptunium (93) with calcium or bismuth (83) and zinc (30).
Why do they need?
Why get new elements, if the process is so long and complicated, and they live in tenths of a second? One explanation: because we can. Experimental evidence of earlier scientific predictions strengthens the position of the other predictions and enables further assumptions. The second explanation is that science can open up a whole group of new superheavy elements, which will be long-lived, and therefore useful – it is assumed that they can get practical applications in the field of nuclear weapons, energy, as well as provide a basis for materials Superproperty. The existence of such elements predicted by the theory of the “island of stability”.
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