Holmiu
67
Ho
Grupă
n/a
Perioadă
6
Bloc
f
Protoni
Electroni
Neutroni
67
67
98
Proprietăți Generale
Număr atomic
67
Masă atomică
164,93032
Numar de masa
165
Categorie
Lantanide
Culoare
Argint
Radioactive
Nu
Din cuvântul latin Holmia, însemnând Stockholm
Structură cristalină
Sistemul Hexagonal
Istoric
Holmium was discovered by Swiss chemists Marc Delafontaine and Jacques-Louis Soret in 1878.
They noticed the aberrant spectrographic absorption bands of the then-unknown element.
Later in 1878, Per Teodor Cleve independently discovered the element while he was working on erbia earth.
They noticed the aberrant spectrographic absorption bands of the then-unknown element.
Later in 1878, Per Teodor Cleve independently discovered the element while he was working on erbia earth.
Electroni pe nivelul de energie
2, 8, 18, 29, 8, 2
Configurație electronică
[Xe] 4f11 6s2
Holmium has the highest magnetic strength of any naturally occurring element
Proprietăți Fizice
Fază
Solid
Densitate
8,795 g/cm3
Punct de topire
1734,15 K | 1461 °C | 2661,8 °F
Punct de fierbere
2993,15 K | 2720 °C | 4928 °F
Energie de fuziune
17 kJ/mol
Energie de evaporare
265 kJ/mol
Căldură specifică
0,165 J/g·K
Abundența în scoarța Pământului
0,00012%
Abundența în Univers
5×10-8%
Numarul CAS
7440-60-0
Număr CID PubChem
23988
Proprietăți Atomice
Rază atomică
176 pm
Rază de covalență
192 pm
Electronegativitate
1,23 (Scara lui Pauling)
Potențial de ionizare
6,0215 eV
Volum molar
18,7 cm3/mol
Conductivitate termică
0,162 W/cm·K
Număr de oxidare
3
Aplicații
Holmium is used to create the strongest artificially generated magnetic fields, when placed within high-strength magnets as a magnetic pole piece.
It is one of the colorants used for cubic zirconia and glass, providing yellow or red coloring.
Holmium isotopes are good neutron absorbers and are used in nuclear reactor control rods.
It is one of the colorants used for cubic zirconia and glass, providing yellow or red coloring.
Holmium isotopes are good neutron absorbers and are used in nuclear reactor control rods.
Holmium is considered to be of low toxicity
Izotopi
Izotopi stabili
165HoIzotopi instabili
140Ho, 141Ho, 142Ho, 143Ho, 144Ho, 145Ho, 146Ho, 147Ho, 148Ho, 149Ho, 150Ho, 151Ho, 152Ho, 153Ho, 154Ho, 155Ho, 156Ho, 157Ho, 158Ho, 159Ho, 160Ho, 161Ho, 162Ho, 163Ho, 164Ho, 166Ho, 167Ho, 168Ho, 169Ho, 170Ho, 171Ho, 172Ho, 173Ho, 174Ho, 175Ho