Tc
98.000Technetium
Teknesyum
Technetium is a radioactive transition metal with atomic number 43. It was the first artificially produced element and is best known for technetium-99m, the diagnostic radioisotope used in nuclear medicine.
43
98 g/mol
[Kr] 4d⁵ 5s²
2 | 8 | 18 | 13 | 2
1.9
11.5 g/cm³
2156.8 °C
4264.9 °C
Carlo Perrier & Emilio Segrè
Technetium was synthesized in 1937 by Carlo Perrier and Emilio Segrè after Mendeleev’s predicted eka-manganese gap had remained empty. Its name comes from a Greek word meaning artificial.
Technetium-97
Half-life: About 4.21 million years. Long-lived radioactive isotope of technetium; older secondary summaries may round differently.Technetium-98
Half-life: About 4.2 million years. Long-lived radioactive isotope of technetium; some reference tables report higher rounded values.Technetium-99
Half-life: About 211,000 years. Long-lived fission product and decay product of technetium-99m.Technetium-99m
Half-life: About 6 hours. Metastable gamma emitter used in diagnostic nuclear medicine.TcO₄⁻
Pertechnetate IonRadiopharmaceutical precursor and diagnostic imaging species.Tc₂O₇
Technetium HeptoxideResearch compound and strong oxidizing technetium oxide.- Technetium-99m radiopharmaceuticals for diagnostic medical imaging
- Pertechnetate imaging of thyroid and other tissues
- Bone, heart, kidney and lung scans using labeled technetium compounds
- Nuclear chemistry research and tracer studies
Technetium has no biological role. All technetium isotopes are radioactive.
- Technetium was the first element to be produced artificially.
- No isotope of technetium is stable.
- Technetium-99m emits gamma radiation suitable for medical imaging and has a short half-life.
- Trace natural technetium can occur from uranium fission, but it is not a stable primordial element.
- Technetium has atomic number 43 and belongs to group 7.
- Its electron configuration is [Kr] 4d⁵ 5s².
- Technetium and promethium are the two elements below bismuth with no stable isotopes.
- Technetium-99m comes from molybdenum-99 generators in medical use.
What is the atomic number of technetium?
The atomic number of technetium is 43.
What is the atomic mass of technetium?
Technetium has no stable isotopes; many periodic tables list its relative atomic mass as about 98.
What is the electron configuration of technetium?
Technetium has the electron configuration [Kr] 4d⁵ 5s².
Does technetium have stable isotopes?
No. All technetium isotopes are radioactive.
What is technetium used for?
Technetium is mainly used as technetium-99m in diagnostic nuclear medicine imaging.
What is technetium-99m?
Technetium-99m is a short-lived metastable isotope that emits gamma rays useful for medical imaging.
Why is technetium called the first artificial element?
It filled a periodic table gap after being synthesized in a laboratory before being found in meaningful natural amounts.