In chemistry, transactinide elements are the chemical elements with atomic numbers greater than 103, the atomic number of lawrencium. They are also called super-heavy elements. Chemistry (in Greek: χημεία) is the science of matter and its interactions with energy and itself (see physics, biology). ... A chemical element, often called simply element, is a substance that cannot be divided or changed into different substances by ordinary chemical methods. ... The atomic number (Z) is a term used in chemistry and physics to represent the number of protons found in the nucleus of an atom. ... Known properties Name, Symbol, Number lawrencium, Lr, 103 Chemical series Transition metals Group, Period, Block 3, 7, d Appearance unknown; probably metallic, silvery white or gray Atomic weight [ 262 ] amu Electron configuration probably [Rn]5f14 6d1 7s2 e- s per energy level 2, 8, 18, 32, 32, 9, 2 State...

All transactinide elements are also transuranium elements, that is, have an atomic number greater than that of uranium. The further distinction of having a greater atomic number than the actinides is significant in several ways: In chemistry, transuranium elements (also known as transuranic elements) are the chemical elements with atomic numbers greater than 92, the atomic number of Uranium. ... General Name, Symbol, Number uranium, U, 92 Chemical series actinides Group, Period, Block ?, 7, f Appearance silvery gray metallic Atomic mass 238. ...

• The transactinide elements all have electrons in the 6d subshell in their ground state (and thus are placed in the d-block), although lawrencium also has one electron in the 6d subshell.
• The Element naming controversy involved the first five or six transactinide elements. These elements thus used three-letter systematic names for many years.
• Except for dubnium, even the longest-lasting isotopes of transactinide elements have extremely short half-lives, measured in seconds, or smaller units.

All of the transactinide elements are radioactive and have only been obtained synthetically in the laboratory. None of these elements has ever been collected in a macroscopic sample. Transactinide elements are all named after either nuclear physicists or important locations involved in the synthesis of the elements. In atomic physics, an electron subshell is a group of atomic orbitals with the same values of the principal quantum number n and the angular momentum quantum number l. ... D Block is a rap group based in Yonkers, New York. ... The names for the chemical elements 104 to 108 have been the subject of a major controversy starting in the 1960s which was only finally resolved in 1997. ... In chemistry, heavy transuranic elements receive a permanent name and symbol only after their discovery has been confirmed. ... Known properties Name, Symbol, Number dubnium, Db, 105 Chemical series Transition metals Group, Period, Block 5, 7, d Appearance unknown; probably metallic, silvery white or gray Atomic weight [262] amu Electron configuration probably [Rn]5f14 6d3 7s2 e- s per energy level 2, 8, 18, 32, 32, 11, 2 State... Radioactive decay is the set of various processes by which unstable atomic nuclei (nuclides) emit subatomic particles (radiation). ...

The term transactinide is an adjective, and is not commonly used alone as a noun to refer to the transactinide elements.

List of the transactinide elements:

• 104 Rutherfordium, Rf
• 105 Dubnium, Db
• 106 Seaborgium, Sg
• 107 Bohrium, Bh
• 108 Hassium, Hs
• 109 Meitnerium, Mt
• 110 Darmstadtium, Ds
• 111 Roentgenium, Rg
• 112 Ununbium, Uub*
• 113 Ununtrium, Uut*
• 114 Ununquadium, Uuq*
• 115 Ununpentium, Uup*
• 116 Ununhexium, Uuh*

*The existence of these elements has been confirmed, however the names and symbols given are provisional as no names for the elements have been agreed on. Known properties Name, Symbol, Number Rutherfordium, Rf, 104 Chemical series Transition metals Group, Period, Block 4, 7 , d Appearance unknown Atomic weight [261] amu Electron configuration probably [Rn]5f14 6d2 7s2 e- s per energy level 2,8,18,32,32,10,2 State of matter Presumably a solid Rutherfordium... Known properties Name, Symbol, Number dubnium, Db, 105 Chemical series Transition metals Group, Period, Block 5, 7, d Appearance unknown; probably metallic, silvery white or gray Atomic weight [262] amu Electron configuration probably [Rn]5f14 6d3 7s2 e- s per energy level 2, 8, 18, 32, 32, 11, 2 State... Known properties Name, Symbol, Number seaborgium, Sg, 106 Chemical series Transition metals Group, Period, Block 6, 7 , d Appearance unknown Atomic weight [266] amu Electron configuration probably [Rn]5f14 6d4 7s2 e- s per energy level 2, 8, 18, 32, 32, 12, 2 State of matter presumably a solid Seaborgium... Known properties Name, Symbol, Number Bohrium, Bh, 107 Chemical series Transition metals Group, Period, Block 7, 7, d Appearance unknown; probably metallic, silvery white or gray Atomic weight [264] amu Electron configuration probably [Rn]5f14 6d5 7s2 e- s per energy level 2, 8, 18, 32, 32, 13, 2 State... Known properties Name, Symbol, Number Hassium, Hs, 108 Chemical series Transition metals Group, Period, Block 8, 7, d Appearance unknown Atomic weight [269] amu Electron configuration probably [Rn] 5f14 6d6 7s2 a guess based osmium e- s per energy level 2, 8, 18, 32, 32, 14, 2 State of matter... Known properties Name, Symbol, Number meitnerium, 109, Mt Chemical series Transition metals Group, Period, Block 9, 7, d Appearance unknown Atomic weight [268] amu Electron configuration probably [Rn] 5f14 6d7 7s2 e- s per energy level 2, 8, 18, 32, 32, 15, 2 State of matter Presumably a solid Meitnerium... Known properties Name, Symbol, Number Darmstadtium, Ds, 110 Chemical series Transition metals Group, Period, Block 10, 7, d Appearance unknown Atomic weight From [267] amu to [281] amu Electron configuration probably [Rn] 5f14 6d9 7s1 a guess based upon platinum e- s per energy level 2, 8, 18, 32, 32... General Name, Symbol, Number roentgenium, Rg, 111 Chemical series transition metals Group, Period, Block 11, 7, d Appearance unknown, probably silvery white or metallic gray Atomic mass (272) g/mol Electron configuration probably [Rn] 5f14 6d10 7s1 Electrons per shell 2, 8, 18, 32, 32, 18, 1 Phase presumably a... Known properties Name, Symbol, Number Ununbium, Uub, 112 Chemical series Transition metal Group, Period, Block 12, 7, d Appearance Unknown, probably a metallic and silvery white or grey colour. ... Predicted properties Name, Symbol, Number Ununtrium, Uut, 113 Chemical series Presumably poor metals Group, Period, Block 13, 7 , p Appearance Unknown Atomic weight [284] amu (A guess) Electron configuration [Rn] 5f14 6d10 7s27p1 (A guess based upon thallium) e- s per energy level 2, 8, 18, 32, 32, 18, 3... Known properties Name, Symbol, Number Ununquadium, Uuq, 114 Chemical series Presumably poor metals Group, Period, Block 14, 7, p Appearance Unknown, probably a metallic and silvery white or grey colour Atomic weight [289] amu Supposed half-life 30 seconds Electron configuration [Rn] 5f14 6d10 7s27p2 (a guess based upon radon... Predicted properties Name, Symbol, Number ununpentium, Uup, 115 Chemical series presumably poor metals Group, Period, Block 15, 7 , p Appearance unknown Atomic weight [288] amu (a guess) Electron configuration [Rn] 5f14 6d10 7s27p3 (a guess based upon bismuth) e-s per energy level 2, 8, 18, 32, 32, 18, 5... Predicted properties Name, Symbol, Number Ununhexium, Uuh, 116 Chemical series Presumably poor metals Group, Period, Block 16, 7 , p Appearance Unknown, probably a metallic and silvery white or grey color Atomic weight [292] amu Electron configuration [Rn] 5f14 6d10 7s27p4 (a guess based upon polonium) e-s per energy level...

See also

• Transuranium element
• Bose-Einstein condensate (also known as Superatom)
• Island of stability