Holmium

67
Ho
Golongan
n/a
Periode
6
Blok
f
Proton
Elektron
Neutron
67
67
98
Sifat Umum
Nomor atom
67
Massa atom
164,93032
Nomor massa
165
Kategori
Lantanida
Warna
Perak
Radioaktif
Tidak
From the Latin word Holmia meaning Stockholm
Struktur kristal
Segienam Sederhana
Sejarah
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.
Elektron per kulit
2, 8, 18, 29, 8, 2
Konfigurasi elektron
[Xe] 4f11 6s2
Ho
Holmium has the highest magnetic strength of any naturally occurring element
Sifat Fisika
Fase
Solid
Kepadatan
8,795 g/cm3
Titik lebur
1734,15 K | 1461 °C | 2661,8 °F
Titik didih
2993,15 K | 2720 °C | 4928 °F
Kalor peleburan
17 kJ/mol
Kalor penguapan
265 kJ/mol
Kapasitas kalor molar
0,165 J/g·K
Kelimpahan di kerak bumi
0,00012%
Kelimpahan di alam semesta
5×10-8%
Ultrapure
Kredit Gambar: Images-of-elements
Ultrapure holmium
Nomor CAS
7440-60-0
PubChem CID Number
23988
Sifat Atom
Jari-jari atom
176 pm
Jari-jari kovalen
192 pm
Elektronegativitas
1,23 (Skala Pauling)
Potensi Ionisasi
6,0215 eV
Volume atom
18,7 cm3/mol
Kondusivitas termal
0,162 W/cm·K
Bilangan oksidasi
3
Aplikasi
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
Isotop
Isotop stabil
165Ho
Isotop tidak stabil
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