Technetium 

Atomic number: 43

Symbol: Tc

Category: transition metal

Density at 25°C: solid:  11 g·cm−3

As the name suggests this is the first transition metal that was created. There is nothing stable about this element, all forms are radioactive.  Only trace amounts are found in nature. 99Tc is the most common isotope used in medical tracing applications. It releases low energy electrons. 


A button of technetium. image: adapted from wikipedia


Use, natural applications or common combinations: 

  • Medicine as a tracer
  • Used for calibration of detectors
  • can be used as a catalyst


Basic characteristics:

  • Standard atomic weight: not really used but around 98
  • Melting point: 2157 °C
  • Boiling point: 4265 °C
  • Radioactivity: no isotopes stable
  • 99Tc has half life of 2.111×105 y emitting low energy electrons.