has quality atom radioactive quality nihonium atom Nihonium is a synthetic chemical element with the symbol Nh and atomic number 113. It is extremely radioactive; its most stable known isotope, nihonium-286, has a half-life of about 10 seconds. In the periodic table, nihonium is a transactinide element in the p-block. It is a member of period 7 and group 13 (boron group). nihonium Nh https://en.wikipedia.org/wiki/Nihonium nihonio nihonio 钅尔 Nihonium nihonium