|Name in Saurian|| Sxutnasbaim (Sx)|
|Systematic name|| Untrioctium (Uto)|
|Location on the periodic table|
|Previous element||Feynmanium (137Fy)|
|Next element||Astonium (139An)|
|Atomic mass||380.1508 u, 631.2552 yg|
|Atomic radius||163 pm, 1.63 Å|
|Van der Waals radius||171 pm, 1.71 Å|
|Nucleons||377 (138 p+, 239 n0)|
|Nuclear radius||8.63 fm|
|Electron configuration|| [Mc] 5g12 6f3 7d1 8s2 8p2|
2, 8, 18, 32, 44, 21, 9, 4
|Oxidation states|| +4, +5|
(mildly basic oxide)
|First ionization energy||638.3 kJ/mol, 6.615 eV|
|Electron affinity||164.0 kJ/mol, 1.699 eV|
|Covalent radius||188 pm, 1.88 Å|
|Molar mass||380.151 g/mol|
|Molar volume||52.933 cm3/mol|
|Atomic number density||1.14 × 1022 cm−3|
|Average atomic separation||445 pm, 4.45 Å|
|Speed of sound||4016 m/s|
|Crystal structure||Face centered cubic|
|Melting point|| 701.57 K, 428.42°C|
|Boiling point|| 1065.81 K, 792.66°C|
|Liquid range||364.24 K/°C, 655.63°F/°R|
|Triple point|| 700.57 K, 427.42°C|
@ 51.243 Pa, 0.38435 torr
|Critical point|| 2798.51 K, 2525.36°C|
@ 605.2591 MPa, 5973.462 atm
|Heat of fusion||6.668 kJ/mol|
|Heat of vaporization||118.528 kJ/mol|
|Heat capacity|| 0.05386 J/g/K, 0.09695 J/g/°R|
20.476 J/mol/K, 36.856 J/mol/°R
|Universe (by mass)|| Relative: 7.90 × 10−31|
Absolute: 2.65 × 1022 kg
Chadwickium is the fabricated name of a hypothetical element with the symbol Ch and atomic number 138. Chadwickium was named in honor of James Chadwick (1891–1974), who discovered a neutron. This element is known in scientific literature as untrioctium (Uto), or simply element 138. Chadwickium is the eighteenth element of the lavoiside series and located in periodic table coordinate 5g18.
Chadwickium is a silvery white metal that is lusterous, malleable, and ductile like most metals. Chadwickium has a density of 7.2 g/cm3 and its speed of sound is 4016 m/s. There are 11.4 sextillion atoms in one cubic centimeter of chadwickium and 320 septillion in one cubic foot.
Its melting point is 1263°R (702 K), and its boiling point is 1918°R (1066 K), making its liquid range of 655°R (364 K), which is narrow for a metal, slightly narrower than mercury's. Like temperature, the liquid state is only stable between a certain range of pressure, between the triple point and critical point. Liquid state would be nonexistent below the triple point while liquid state would be indistinguishable above the critical point. For the metal, the triple point is 1261°R (701 K), very close to its melting point, and a pressure of 51.24 Pa. Its critical point is 5037°R (2799 K) and 605.26 MPa.
Chadwickium contains 377 nucleons, or particles that make up the nucleus comprising of protons and neutrons. Surrounding the nucleus, there are 8 shells and 24 orbitals. Assumely, the 5g orbital should be completed with 18 electrons, but actually there are twelve due to spin-orbit coupling due to relativistic effects. The six missing electrons in the 5g orbital are located in different orbitals in different shells, half are in a shell one beyond the 5g orbital at 6f orbital, while the rest are in two outermost shells, one in 7d and two in 8p.
Like every other elements heavier than lead, chadwickium has no stable isotopes. The most stable isotope is 377Ch with a half-life of 16 hours, undergoing cluster decays to 332Pl by emitting 10B and 20Ne as well as 30 neutrons. Every remaining isotopes have half-lives under 30 minutes while majority of these under a minute. Chadwickium has meta states, the most stable is 376mCh (t½ = 40.5 seconds).
Chadwickium's oxidation states are +4 and +5. Ch4+ has the electron configuration of elemental chadwickium minus 8s2 and 8p1/2, while Ch5+ has the electron configuration of Ch4+ minus 7d1. With the electronegativity of 1.48, it is little reactive. Due to Ch4+ being stable while O2− the most common oxygen ion and the most abundant supply of oxygen is O2, then that molecule simply bond to chadwickium to form ChO2 by exposure to air where O2 is abundant.
Chadwickium(IV) oxide (ChO2), can be made by simply putting the metal in place where there's air, literally anywhere but beyond Earth. This metal can even react with water to form chadwickium(IV) hydroxide (Ch(OH)4). This metal dissolves and reacts with strong acids such as hydrochloric acid to form chadwickium(IV) chloride (ChCl5) and sulfuric acid to form chadwickium sulfate (Ch(SO4)2).
Occurrence and synthesis Edit
It is certain that chadwickium is virtually nonexistent on Earth, and is extremely rare in the universe. Since every element heavier than lithium were produced by stars, then chadwickium must be produced in stars, and then thrown out into space by exploding stars. But it is virtually impossible for even the most powerful supernovae or most violent neutron star collisions to produce this element through r-process because there's not enough energy available or not enough neutrons, respectively, to produce this heavy element. Instead, this element can only practically be made by advanced technological civilizations. An estimated abundance of chadwickium in the universe by mass is 7.90 × 10−31, which amounts to 2.65 × 1022 kilograms or over ⅓ Lunar masses worth of this element.
To go along with other such civilizations, humans on Earth may eventually have the capability to synthesize chadwickium. To synthesize most stable isotopes of chadwickium, nuclei of a couple lighter elements must be fused together, and right amount of neutrons must be seeded. This operation would be extremely difficult since it requires vast amounts of energy. Here's couple of example equations in the production of the most stable isotope 377Ch.