Holmium

67
Ho
Gruppe
n/a
Periode
6
Blok
f
Protons
Electrons
Neutrons
67
67
98
General Properties
Atomnummer
67
Atommasse
164,93032
Mass Number
165
Kategori
Lantanider
Farve
Silver
Radioactive
Nej
From the Latin word Holmia meaning Stockholm
Krystalstruktur
Simpel Hexagonal
History
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.
Elektroner i hver skal
2, 8, 18, 29, 8, 2
Elektronkonfiguration
[Xe] 4f11 6s2
Ho
Holmium has the highest magnetic strength of any naturally occurring element
Physical Properties
Tilstandsform
Fast stof
Massefylde
8,795 g/cm3
Smeltepunkt
1734,15 K | 1461 °C | 2661,8 °F
Kogepunkt
2993,15 K | 2720 °C | 4928 °F
Smeltevarme
17 kJ/mol
Fordampningsvarme
265 kJ/mol
Varmefylde
0,165 J/g·K
Abundance in Earth's crust
0,00012%
Abundance in Universe
5×10-8%
Ultrapure
Billede akkrediteringer: Images-of-elements
Ultrapure holmium
CAS Number
7440-60-0
PubChem CID Number
23988
Atomic Properties
Atomradius
176 pm
Kovalent radius
192 pm
Elektronegativitet
1,23 (Paulings skala)
Ionization Potential
6,0215 eV
Atomic Volume
18,7 cm3/mol
Varmeledningsevne
0,162 W/cm·K
Oxidationstrin
3
Applications
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.
Holmium is considered to be of low toxicity
Isotoper
Stable Isotopes
165Ho
Unstable Isotopes
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