Teknetium

Kemiallinen merkki: Tc
Järjestysluku: 43
Kategoria: siirtymämetallit
Ryhmä: 7
Jakso: 5
Lohko: d
Moolimassa: [98] g/mol
Elektronia kuorilla: 2, 8, 18, 13, 2
CAS-numero: 7440-26-8
Olomuoto: kiinteä
Tiheys: 11 kg/l (lähellä huoneenlämpöä)
Sulamispiste: 2430 K (2157 °C, 3915 °F)
Kiehumispiste: 4538 K (4265 °C, 7709 °F)
Kiderakenne: hexagonal
Hapetusluvut: 7, 6, 5, 4, 3, 1
Elektronegatiivisuus: 1,9 (Pauling-asteikko)
Nimen alkuperä: technitos (Greek)
Nimen tarkoitus: artificial, since technetium was the first element to be artificially produced
Faktoja:
- on Earth, technetium occurs in trace but measurable quantities as a product of spontaneous fission in uranium ore or by neutron capture in molybdenum ores
- is a silvery-grey radioactive metal with an appearance similar to platinum
- plays no natural biological role and is not normally found in the human body
- technetium-98 has a half-life of 4,2 million years
- technetium-99m (the m indicates that this is a metastable nuclear isomer) is used in radioactive isotope medical tests, for example as a radioactive tracer that medical equipment can detect in the human body