Atomic number 43
Technetium
Transition metal
In the real world
Quick facts
- Atomic mass
- 98.000
- Group
- 7
- Period
- 5
- State (STP)
- solid
- Electronegativity
- 1.90
- Common ox. states
- +4, +7
Properties
Electron configuration
[Kr] 4d⁵ 5s²
- Ionization energy
- 702.0 kJ/mol
- Electron affinity
- 53.0 kJ/mol
- Melting point
- 2430.00 K (2156.8 °C)
- Boiling point
- 4538.00 K (4264.9 °C)
How dangerous is it?
4/5 · Severe
A man-made element with no stable form, so every sample is radioactive. It is handled only in licensed labs and is never something you would meet day to day.
- RadioactiveImmediate and cumulative
Every isotope is radioactive, giving off radiation that can harm living cells. (a man-made element that does not occur naturally in usable amounts)
Worked with only in licensed labs behind shielding, with monitoring and strict limits.
How it bonds
Technetium was the first element produced artificially (1937) - its name is from the Greek for "artificial." All isotopes are radioactive. Tc-99m is the workhorse of medical imaging (about 80% of nuclear-medicine scans). Mirrors manganese chemistry (+4, +7).
