Quick answerTechnetium (Tc) is a transition metal with atomic number 43 and a mass number of 98 (the most stable isotope), in group 7, period 5. It was discovered by Carlo Perrier and Emilio Segrè in 1937. It is used for medical imaging and nuclear medicine. Its electron configuration is [Kr] 4d5 5s2.
Technetium is the lightest element with no stable isotopes, and its short-lived form images hearts and bones in hospitals worldwide.
Key facts
| Symbol | Tc |
|---|---|
| Atomic number | 43 |
| Atomic mass | [98] — mass number of the most stable isotope |
| Category | transition metal |
| Group | 7 |
| Period | 5 |
| Block | d-block |
| Electron configuration | [Kr] 4d5 5s2 |
| Discovered | Carlo Perrier and Emilio Segrè, 1937 |
| Uses | medical imaging, nuclear medicine, industrial radiography, research, corrosion inhibition |
Quick quiz
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Keep exploring
- Periodic table — all 118 elements
- Zinc (Zn) — another transition metal, atomic number 30
- Yttrium (Y) — another transition metal, atomic number 39
- Zirconium (Zr) — another transition metal, atomic number 40
- Niobium (Nb) — another transition metal, atomic number 41
- Molybdenum (Mo) — another transition metal, atomic number 42
- Ruthenium (Ru) — another transition metal, atomic number 44
- Rhodium (Rh) — another transition metal, atomic number 45
- Palladium (Pd) — another transition metal, atomic number 46
- Silver (Ag) — another transition metal, atomic number 47
- Cadmium (Cd) — another transition metal, atomic number 48
- All transition metal elements — on the periodic table
Sources & last updated
- CIAAW — Standard Atomic Weights
- PubChem Periodic Table
- Wikipedia — Timeline of chemical element discoveries
Last updated: . Figures are shown with their year; where sources disagree, the value is left out rather than estimated.