Nihonium (Nh)
Nihonium (Nh) is a synthetic and highly radioactive element with the atomic number 113 and a relative atomic mass of 286. It was first created in 2004, 2005, and 2012 by a team at the Riken Nishina Center for Accelerator-based Science in Japan, utilizing advanced techniques such as linear accelerators and cyclotrons to bombard bismuth and americium with ions. Officially recognized by the International Union of Pure and Applied Chemistry (IUPAC) in 2016, nihonium's name derives from the Japanese word "nihon," meaning "Japan," highlighting its significance as the first element discovered in an Asian country.
Nihonium belongs to Group 13 and Period 7 of the periodic table and is theorized to be a solid at room temperature, though its melting point and other physical properties remain largely unknown due to its instability and rapid decay. The most stable isotope, nihonium-286, has a half-life of approximately twenty seconds and decays through alpha decay into roentgenium-282. While its chemical properties are not well studied, it is expected to share similarities with other elements in its group, such as thallium and aluminum. However, due to the limited production of nihonium, no practical applications have been identified outside of basic scientific research.
Subject Terms
Nihonium (Nh)
- Element Symbol: Nh
- Atomic Number: 113
- Atomic Mass: [286]
- Group # in Periodic Table: 13
- Group Name: No information
- Period in Periodic Table: 7
- Block of Periodic Table: p-block
- Discovered by: Riken Nishina Center for Accelerator-based Science (2004)
Nihonium (Nh) is a synthetic, highly radioactive element. Its atomic number is 113, and its relative atomic mass is 286. It was created in 2004, 2005, and 2012 by a team of scientists at the Riken Nishina Center for Accelerator-based Science in Japan. In the late 1980s, Kosuke Morita and his team at Riken used a linear accelerator and ion separator to research new elements. During this time, his team mounted an attempt to form element 113. They bombarded the atoms of the element bismuth with zinc ions traveling at approximately 10 percent the speed of light. The resulting atoms decayed into dubnium-262 through alpha decay.
Element 113 was also discovered in 2004 by two groups of scientists, one working at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia, and another one at the US Department of Energy’s Lawrence Livermore National Laboratory. During their experiments, the scientists bombarded atoms of the element americium-243 with the ions of calcium-48 through a machine known as a cyclotron. This process produced one atom of moscovium-287 and three atoms of moscovium-288. All four atoms thus produced quickly decayed from moscovium into nihonium through alpha decay.
In the periodic table, nihonium is placed between the elements copernicium and flerovium. It falls in Group 13 and Period 7 of the p-block in the periodic table. Its electronic configuration is [Rn] 5f146d107s27p1.
Often, there is competition between researchers for the discovery and naming of elements. Ununtrium, with a chemical symbol of Uut, was a provisional name given to element 113 by the International Union of Pure and Applied Chemistry (IUPAC) until the designated officials proposed a final name. In December 2015, Morita, the lead researcher at the Riken facility, was notified that the center had met the benchmarks for naming element 113. The Riken group proposed the name japonium (Jp). Another potential name—rikenium (Rk)—was proposed as a way to honor the name of the Riken facility. Scientists at the Joint Institute for Nuclear Research in Russia and at the Lawrence Livermore National Laboratory in the United States also contested the naming rights of element 113. In January 2016, the IUPAC formally confirmed the existence of the element. That June, it approved the Riken team's proposal of nihonium (from the word nihon, meaning "Japan" in Japanese) and its symbol, Nh, in recognition of the first element to be discovered in an Asian nation.
Physical Properties
Because nihonium is a radioactive and highly unstable element that decays quickly, very little is known about its properties. The standard state of an element is defined as its state at 298 kelvins (K), or 25 degrees Celsius. It is theorized that nihonium is a solid at this temperature. Its melting point, boiling point, and density are not known at this time. No other physical properties of the element are known yet.
Chemical Properties
The most stable isotope of this element is nihonium-286, with a half-life of twenty seconds. This isotope undergoes alpha decay to become roentgenium-282. Alpha decay is a type of radioactive decay in which an unstable atom becomes more stable by losing two protons and two neutrons. These two protons and two neutrons together are called an alpha particle. In this process, a bigger, more unstable nucleus becomes a smaller, more stable nucleus. There is no clear information available as to how many isotopes of nihonium exist. No other chemical properties have been identified yet due to the element’s short half-life, but it is predicted that the properties must be similar to the elements in the same block in the periodic table, such as boron, thallium, aluminum, and some others.
Applications
Because only a few atoms of nihonium have ever been produced, as of 2016, there are no known applications for it outside of basic research.
Bibliography
"Alpha Decay." Glossary. Jefferson Lab, n.d. Web. 11 Feb. 2016.
"The Element Ununtrium." It’s Elemental. Jefferson Lab, n.d. Web. 11 Feb. 2016.
Greenwood, Norman N., and Alan Earnshaw. Chemistry of the Elements. 2nd ed. Portsmouth: Butterworth-Heinemann, 1997. Print.
"The Importance of Nihonium." Japan Times. Japan Times, 25 June 2016. Web. 7 July 2016.
"IUPAC Is Naming the Four New Elements Nihonium, Moscovium, Tennessine, and Oganesson." International Union of Pure and Applied Chemistry. IUPAC, 8 June 2016. Web. 1 July 2016.
"Nihonium." Chemicool Periodic Table. Chemicool.com, 11 June 2016. Web. 7 July 2016.
"Synthetic Radioactive Element 113 Will Be Named by Japanese Researchers." CBC News, Technology & Science. CBC/Radio-Canada, 1 Jan. 2016. Web. 11 Feb. 2016.
"Ununtrium." Elementymology & Elements Multidict. Van der Krogt, n.d. Web. 11 Feb. 2016.
"Ununtrium." The Periodic Table. Royal Soc. of Chemistry, n.d. Web. 11 Feb. 2016.