Unbihexium, also known as element 126 or eka-plutonium, is the possible chemical element with atomic number 126 and placeholder symbol Ubh. "Unbihexium" and "Ubh" are the temporary IUPAC name and symbol, until the element is discovered, confirmed, and a permanent name is decided upon. In the periodic table, unbihexium is expected to be a g-block superactinide and the eighth element in the 8th period.