Osmium

76
Os
Golongan
8
Periode
6
Blok
d
Proton
Elektron
Neutron
76
76
114
Sifat Umum
Nomor atom
76
Massa atom
190,23
Nomor massa
190
Kategori
Logam transisi
Warna
Biru Keabu-abuan
Radioaktif
Tidak
From the Greek word osme, meaning smell
Struktur kristal
Segienam Sederhana
Sejarah
Osmium was discovered in 1803 by English chemist Smithson Tennant in London.

Chemists who studied platinum dissolved it in aqua regia to create soluble salts and observed a small amount of a dark, insoluble residue.

Smithson Tennant analyzed the insoluble residue and concluded that it must contain a new metal.
Elektron per kulit
2, 8, 18, 32, 14, 2
Konfigurasi elektron
[Xe] 4f14 5d6 6s2
Os
Osmium is the least abundant stable element in the Earth's crust
Sifat Fisika
Fase
Solid
Kepadatan
22,61 g/cm3
Titik lebur
3306,15 K | 3033 °C | 5491,4 °F
Titik didih
5285,15 K | 5012 °C | 9053,6 °F
Kalor peleburan
31 kJ/mol
Kalor penguapan
630 kJ/mol
Kapasitas kalor molar
0,13 J/g·K
Kelimpahan di kerak bumi
1,8×10-7%
Kelimpahan di alam semesta
3×10-7%
Osmium
Kredit Gambar: Wikimedia Commons (Alchemist-hp)
Osmium crystals produced by chemical transport reaction in chlorine gas
Nomor CAS
7440-04-2
PubChem CID Number
23937
Sifat Atom
Jari-jari atom
135 pm
Jari-jari kovalen
144 pm
Elektronegativitas
2,2 (Skala Pauling)
Potensi Ionisasi
8,4382 eV
Volume atom
8,49 cm3/mol
Kondusivitas termal
0,876 W/cm·K
Bilangan oksidasi
-2, 1, 2, 3, 4, 5, 6, 7, 8
Aplikasi
Osmium is used alloyed with other metals in the platinum group to produce very hard alloys.

Osmium alloys are used in the tips of fountain pens, instrument pivots, and electrical contacts

Osmium tetroxide has been used in fingerprint detection and in staining fatty tissue for optical and electron microscopy.
Even low concentrations in air can cause lung congestion, skin damage, or eye damage
Isotop
Isotop stabil
184Os, 187Os, 188Os, 189Os, 190Os, 192Os
Isotop tidak stabil
161Os, 162Os, 163Os, 164Os, 165Os, 166Os, 167Os, 168Os, 169Os, 170Os, 171Os, 172Os, 173Os, 174Os, 175Os, 176Os, 177Os, 178Os, 179Os, 180Os, 181Os, 182Os, 183Os, 185Os, 186Os, 191Os, 193Os, 194Os, 195Os, 196Os