Symbol Tb
Atomic Number 65
Atomic Mass 158.925 g.mol −3
Discovered by Carl Gustav Mosander

Chemical Properties of Terbium

Group Lanthanides Melting point 1359°C
Period 6 Boiling point 3230°C
Block f Density (g cm−3) 8.23
Atomic number 65 Relative atomic mass 158.925
State at 20°C Solid Key isotopes 159Tb
Electron configuration [Xe] 4f6s2 CAS number 7440-27-9
ChemSpider ID 22397 ChemSpider is a free chemical database

What is Iodine?

  • Terbium (Tb) is a chemical element with atomic number 65 represented with the symbol Tb in the periodic table, which was discovered by Carl Mosander in the year 1843.
  • It is named after a village of Ytterby in Sweden.
  • Terbium is a soft, ductile, malleable and very rare element. It is so soft that can be cut with a knife.
  • Tb is stable in air to some extent and oxidizes very slowly. It is attacked by cold water.
  • It has simple ferromagnetic properties at temperatures below 219k. It changes into a helical antiferromagnetic state above 219 k, where all atomic moments in a particular basal plane layer are parallel.
  • It is very rare to find this metal as a free element. Terbium is always available with other rare earth elements like monazite, xenotime, and euxenite. Some of the richest commercial terbium sources are ion adsorption clays of southern China.

Uses or Applications of Iodine

  • It is used as a doping agent in calcium tungstate, calcium fluoride and strontium molybdate which are used in solid-state devices. Works as a crystal stabilizer of fuel cells.
  • Alloys of Terbium are used in the manufacturing of electronic devices like sensors, sound bug devices, and actuators.
  • It is also used in the manufacture of color tv tubes and fluorescent lights.

Environmental Effects of Iodine

  • Terbium has no biological use and has low toxicity. When contacted, it may cause serious irritation to skin and eyes.

Practise This Question

The state in which 99% matter of the Universe exists is