|Name in Saurian|| Xidtaim (Xi)|
|Systematic name|| Unhexnilium (Uhn)|
|Location on the periodic table|
|Above element||Hassium (108Hs)|
|Previous element||Vanderwaalsium (159Vw)|
|Next element||Fraunhoferium (161Fh)|
|Atomic mass||460.8255 u, 765.2187 yg|
|Atomic radius||204 pm, 2.04 Å|
|Van der Waals radius||246 pm, 2.46 Å|
|Nucleons||457 (160 p+, 297 n0)|
|Nuclear radius||9.21 fm|
|Electron configuration|| [Mc] 5g18 6f14 7d5 8s2 8p2 9s1|
2, 8, 18, 32, 50, 32, 13, 4, 1
|Oxidation states|| −1, 0, +1, +2, +3, +4,|
+5, +6, +7, +8, +10
(strongly basic oxide)
|First ionization energy||428.5 kJ/mol, 4.441 eV|
|Electron affinity||88.4 kJ/mol, 0.916 eV|
|Covalent radius||209 pm, 2.09 Å|
|Molar mass||460.825 g/mol|
|Molar volume||12.695 cm3/mol|
|Atomic number density||4.74 × 1022 cm−3|
|Average atomic separation||276 pm, 2.76 Å|
|Speed of sound||4757 m/s|
|Crystal structure||Simple cubic|
|Melting point|| 571.10 K, 297.95°C|
|Boiling point|| 2233.50 K, 1960.35°C|
|Liquid range||1662.40 K/°C, 2992.33°F/°R|
|Triple point|| 571.10 K, 297.95°C|
@ 1.6875 nPa, 1.2657 × 10−11 torr
|Critical point|| 6155.40 K, 5882.25°C|
@ 86.3590 MPa, 852.300 atm
|Heat of fusion||5.117 kJ/mol|
|Heat of vaporization||189.512 kJ/mol|
|Heat capacity|| 0.05560 J/g/K, 0.10008 J/g/°R|
25.623 J/mol/K, 46.122 J/mol/°R
|Universe (by mass)|| Relative: 2.18 × 10−35|
Absolute: 7.31 × 1017 kg
Hundium is the fabricated name of a hypothetical element with the symbol Hu and atomic number 160. Hundium was named in honor of Friedrich Hund (1896–1997), who governed the electron configurations with maximum multiplicity (known as Hund's rules). This element is known in scientific literature as unhexnilium (Uhn), dvi-osmium, or simply element 160. Hundium is the heaviest member of the iron family (below iron, ruthenium, osmium, and hassium) and is the sixth member of the vanthoffide series; this element is located in periodic table coordinate 7d6.
At ordinary conditions, hundium is a purplish gray metal that is ductile, malleable, and lustrous. With the density of 36.3 g/cm3, the element is 1.7 times denser than the other family member platinum (21.45 g/cm3). Hundium atoms forming cubic crystals are close together, at an average distance of just 276 picometers between atoms. Consequently, there are a lot of atoms in one cubic centimeter (47.4 sextillion) of metal compared to other elements.
Like most other metals, hundium is solid at room temperature (298 K, 537°R), most with melting points above 1000 K (1800°R). However the melting point of this metal is only 571 K (1028°R), which is very unlike other elements of the iron family due to its unique electron configuration featuring electron in the 9s orbital beyond five-electron 7d orbital and two-electron 8p orbital. The boiling point is almost four times higher than its melting point, at 2234 K (4020°R).
Because of the extreme relativistic effects, the electron is occupying in the 9s orbital, even though it is a period 8 element. It has 160 electrons in 9 shell and 25 orbitals. Because it has so many shells and orbitals, the atom must be large, but because of the electric forces between so many electrons and so many protons, the atom only measures 134 picometers, almost identical in size to iodine atom, whose radius is 133 pm.
Hundium's atom masses 461 daltons, calculated by adding masses of all of the atomic components altogether. 99.98% of all mass are concentrated in the nucleus, which is tiny compared to the size of the atom. Also the nucleus contains most of atomic particles (at 74%), albeit much more moderate than mass and size of nucleus relative to atom. There are two types of particles that make up the nucleus, protons and neutrons. The nucleus has a ratio of 1.86, meaning it contains 86% more neutrons (297) than protons (160).
This element is near the center of the "second island of stability." Another isotope, 453Hu, has a half-life of 1.35 hours. All of the remaining isotopes have half-lives less than 20 minutes and the majority of these have half-lives less than 20 seconds. Hundium has isomers like more than 90% of elements on the 172-element periodic table. The most stable isomer has a half-life of 2.5 seconds for 454mHu, about 1⁄4000 the half-life of 457Hu. 456mHu has a half-life of 403 milliseconds and 459mHu has a half-life of 13 milliseconds. Every other isomers have half-lives less than a millisecond.
Hundium's most stable oxistate is +1 due to its readiness to give up the only electron in the ninth shell, thus hundium would most commonly form monovalent compounds. There are few other stable states, +2 means giving up the only electron in the 7d5/2 suborbital in addition to in +1 to achieve amperium's electron configuration, +3 means giving up both 8p1/2 suborbital and +1, and +4 means giving up all electrons mentioned. There are higher stable states, +6 and +8. As a result, hundium would have chemical properties similar to alkali metals. Its electronegativity is 0.82 and first ionization energy 4.4 eV, thus making hundium a very reactive element unlike all the lighter cogeners. It would quickly tarnish when exposed to air and would burn brilliant orange when in powdered form. It would react very readily with mineral acids to form salts and with water to form a strong base. When dissolved, it most easily dissociates into hundium (Hu+) ions forming light pink solution.
The examples of oxides are Hu2O, HuO, HuO3 and HuO4. The carbides are Hu4C, Hu2C, Hu2C3 and HuC2. HuCO3 is a white powder form which can be made when hundium(II) oxide reacts with carbon dioxide. Hundium can form halides, the most stable is monohalides, which are HuF, HuCl, HuBr, and HuI. These compounds are ionic comprising of Hu+ and X−.
- Hu2SO4 + 2 C → Hu2S + 2 CO2
Hundium sodium zinc carbon oxide (HuNa2Zn3CO11) is a superconductor if its below 268 K (−5°C, 23°F, 483°R), very near the freezing point of water.
Like almost every other element, hundium can form organic compounds, called organohundium. The examples are Hu(CO)8 (hundium octacarbonyl), Me4Hu (methylhundium), HuC6H5O7 (hundium citrate), and C4H8Cl2Hu (bis(2-chloroethyl)hundium).
Occurrence and synthesis Edit
It is almost certain that hundium doesn't exist on Earth at all, but it is believed to exist somewhere in the universe, at least in very tiny amounts. Since every element heavier than lithium were produced by stars, then hundium must be produced in stars, and then thrown out into space by exploding stars. But it is theoretically 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 virtually can only be made by advanced technological civilizations. An estimated abundance of hundium in the universe by mass is 2.18 × 10−35, amounting to 7.31 × 1017 kilograms.
To go along with other such civilizations, humans on Earth may eventually have the capability to synthesize hundium. To synthesize most stable isotopes of hundium, 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 and even if nuclei of this element were produced would immediately decay due to its brief half-life. Here's couple of example equations in the production of the most stable isotope 457Hu.