Cobalt
27
Co
Grupă
9
Perioadă
4
Bloc
d
Protoni
Electroni
Neutroni
27
27
32
Proprietăți Generale
Număr atomic
27
Masă atomică
58,933195
Numar de masa
59
Categorie
Metale de tranziție
Culoare
Gri
Radioactive
Nu
Din cuvântul german Kobald, drăcușor sau duh rău; deasemenea din greacă cobalos, mină
Structură cristalină
Sistemul Hexagonal
Istoric
Cobalt compounds have been used for centuries to impart a rich blue color to glass, glazes and ceramics.
The element was first isolated by Swedish chemist George Brandt in 1735.
He showed it was the presence of the element cobalt that caused the blue color in glass, not bismuth as previously thought.
The element was first isolated by Swedish chemist George Brandt in 1735.
He showed it was the presence of the element cobalt that caused the blue color in glass, not bismuth as previously thought.
Electroni pe nivelul de energie
2, 8, 15, 2
Configurație electronică
[Ar] 3d7 4s2
Supplemental colbalt is essential in sheep's diets to improve the wools quality
Proprietăți Fizice
Fază
Solid
Densitate
8,86 g/cm3
Punct de topire
1768,15 K | 1495 °C | 2723 °F
Punct de fierbere
3200,15 K | 2927 °C | 5300,6 °F
Energie de fuziune
16,2 kJ/mol
Energie de evaporare
375 kJ/mol
Căldură specifică
0,421 J/g·K
Abundența în scoarța Pământului
0,003%
Abundența în Univers
0,0003%
Credite imagine: Wikimedia Commons (Alchemist-hp)
Pure cobalt chips, electrolytically refined, as well as a high purity cobalt cube for comparison
Numarul CAS
7440-48-4
Număr CID PubChem
104730
Proprietăți Atomice
Rază atomică
125 pm
Rază de covalență
126 pm
Electronegativitate
1,88 (Scara lui Pauling)
Potențial de ionizare
7,881 eV
Volum molar
6,7 cm3/mol
Conductivitate termică
1 W/cm·K
Număr de oxidare
-1, 1, 2, 3, 4, 5
Aplicații
Cobalt is used in the preparation of magnetic, wear-resistant and high-strength alloys.
Cobalt is widely used in batteries and in electroplating.
Radioactive 60Co is used in the treatment of cancer.
A solution of the chloride is used as a sympathetic ink.
Cobalt is widely used in batteries and in electroplating.
Radioactive 60Co is used in the treatment of cancer.
A solution of the chloride is used as a sympathetic ink.
Cobalt and its compounds are considered to be slightly toxic
Izotopi
Izotopi stabili
59CoIzotopi instabili
47Co, 48Co, 49Co, 50Co, 51Co, 52Co, 53Co, 54Co, 55Co, 56Co, 57Co, 58Co, 60Co, 61Co, 62Co, 63Co, 64Co, 65Co, 66Co, 67Co, 68Co, 69Co, 70Co, 71Co, 72Co, 73Co, 74Co, 75Co