Niobiu
41
Nb
Grupă
5
Perioadă
5
Bloc
d
Protoni
Electroni
Neutroni
41
41
52
Proprietăți Generale
Număr atomic
41
Masă atomică
92,90638
Numar de masa
93
Categorie
Metale de tranziție
Culoare
Gri
Radioactive
Nu
Numit după Niobe, fiica lui Tantalu
Structură cristalină
Corp Centrat Cubic
Istoric
Niobium was discovered by the English chemist Charles Hatchett in 1801 and named the new element columbium.
In 1846, German chemist Henrich Rose independently discovered the element and named it niobium.
The metal was first isolated by Swedish scientist Christian Wilhelm Blomstrand in 1864 who reduced the chloride by heating it in a hydrogen atmosphere.
In 1846, German chemist Henrich Rose independently discovered the element and named it niobium.
The metal was first isolated by Swedish scientist Christian Wilhelm Blomstrand in 1864 who reduced the chloride by heating it in a hydrogen atmosphere.
Electroni pe nivelul de energie
2, 8, 18, 12, 1
Configurație electronică
[Kr] 4d4 5s1
Brazil is the leading producer of niobium
Proprietăți Fizice
Fază
Solid
Densitate
8,57 g/cm3
Punct de topire
2750,15 K | 2477 °C | 4490,6 °F
Punct de fierbere
5017,15 K | 4744 °C | 8571,2 °F
Energie de fuziune
26,8 kJ/mol
Energie de evaporare
690 kJ/mol
Căldură specifică
0,265 J/g·K
Abundența în scoarța Pământului
0,0017%
Abundența în Univers
2×10-7%
Numarul CAS
7440-03-1
Număr CID PubChem
23936
Proprietăți Atomice
Rază atomică
146 pm
Rază de covalență
164 pm
Electronegativitate
1,6 (Scara lui Pauling)
Potențial de ionizare
6,7589 eV
Volum molar
10,87 cm3/mol
Conductivitate termică
0,537 W/cm·K
Număr de oxidare
-1, 2, 3, 4, 5
Aplicații
Niobium is used in arc-welding rods for stabilized grades of stainless steel.
Niobium alloys are strong and are often used in pipeline construction.
The metal is used in superalloys for jet engines and heat resistant equipment.
Niobium is found in many medical devices such as pacemakers.
Niobium alloys are strong and are often used in pipeline construction.
The metal is used in superalloys for jet engines and heat resistant equipment.
Niobium is found in many medical devices such as pacemakers.
Some niobium compounds are highly toxic
Izotopi
Izotopi stabili
93NbIzotopi instabili
81Nb, 82Nb, 83Nb, 84Nb, 85Nb, 86Nb, 87Nb, 88Nb, 89Nb, 90Nb, 91Nb, 92Nb, 94Nb, 95Nb, 96Nb, 97Nb, 98Nb, 99Nb, 100Nb, 101Nb, 102Nb, 103Nb, 104Nb, 105Nb, 106Nb, 107Nb, 108Nb, 109Nb, 110Nb, 111Nb, 112Nb, 113Nb