The identity of a chemical element is determined by the number of protons in its nucleus, known as the Atomic Number (\(Z\)). Atoms are composed of protons and neutrons, which reside in the dense nucleus. The number of protons is the defining characteristic of an element. The number of neutrons can vary, which leads to the concept of different forms of the same element called isotopes. The element in question does not occur naturally on Earth.
Identifying the Element by Atomic Number
The identity of a chemical element is determined solely by its Atomic Number (\(Z\)), which is the count of protons in its nucleus. An atom possessing exactly 106 protons corresponds to the element with Atomic Number \(Z=106\). This element is Seaborgium, designated by the chemical symbol Sg. Seaborgium is classified as a synthetic element, meaning it must be created in a laboratory. On the periodic table, Seaborgium is situated in Period 7 and is the fourth member of Group 6, placing it among the transition metals.
Calculating the Isotope Mass
The number of protons identifies the element as Seaborgium, while the number of neutrons determines the specific isotope. Atoms of the same element that have differing numbers of neutrons possess distinct masses. The total number of protons and neutrons in the nucleus gives the Mass Number (\(A\)). The calculation for this specific atomic nucleus is the sum of the 106 protons and the 159 neutrons, yielding a Mass Number of 265. This specific nuclide is therefore identified as Seaborgium-265, conventionally written as \(^{265}\text{Sg}\).
Properties of Seaborgium
Seaborgium-265 is a radioisotope, meaning it is unstable and highly radioactive. Because it is a superheavy element, its atoms rapidly decay into lighter elements. The half-life of Seaborgium-265 is measured at approximately 14.4 seconds. This short duration means the element has no practical applications outside of academic research aimed at understanding nuclear stability.
As a Group 6 transition metal, Seaborgium is expected to exhibit chemical behavior similar to its lighter congeners, Molybdenum (Mo) and Tungsten (W). Chemical experiments have partially confirmed this prediction, showing that Seaborgium forms compounds analogous to those of Tungsten. For instance, a volatile seaborgium hexacarbonyl compound, \(\text{Sg}(\text{CO})_{6}\), has been successfully synthesized and studied in the gas phase.
Creation and Confirmation of Superheavy Elements
Seaborgium, like all superheavy elements, is created artificially in specialized laboratories using powerful particle accelerators. The process involves nuclear fusion, where a beam of lighter ions is accelerated to high speeds and directed to strike a target of a heavier element. The successful synthesis of Seaborgium-265 was achieved in 1994 by bombarding a target of Curium-248 with a beam of Neon-22 ions. This high-energy collision causes the nuclei of the two elements to fuse briefly, creating the new, short-lived superheavy nucleus.
The initial discovery of element 106 was claimed by two separate research teams in 1974: one at the Lawrence Berkeley Laboratory in the United States and another at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia. It took until 1997 for the International Union of Pure and Applied Chemistry (IUPAC) to officially resolve the naming dispute and establish “Seaborgium.” The confirmation process for new superheavy elements is complex and often takes years because only a few atoms are produced at a time, requiring the detection of their unique decay chains to prove their existence.