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Electron configuration of Thulium

Types Of Heat

Electron Configuration Of Thulium The electron configuration of Thulium is [Xe] 4f13 6s2. Thulium is a metallic chemical element belonging to the group of lanthanides, with atomic number 69 and whose symbol is Tm. It is an easily flammable element, with a metallic luster, dense and very rare in the earth’s crust. Today we are going to study a chemical element belonging to our periodic table known as Thulium.

Thulium has electrons per level of: 2, 8, 18, 31, 8.2, i.e.:

  • 2 electrons in its first shell.
  • 8 electrons in its second shell.
  • 18 electrons in its third shell.
  • 31 electrons in its fourth shell.
  • 8 electrons in its fifth shell.
  • 2 electrons in its sixth shell.

Give a total of 69 protons and electrons.

Electron configuration of Thulium

Thulium Setup

Electron Configuration Of Thulium The electron configuration of Thulium is [Xe] 4f13 6s2 which would be represented in detail as follows:

1s2 2s2 2s6 3s2 3s6 3d10 4s2 4s6 4d10 5s2 5s6 4f13 5d0 6s2


Thulium was discovered in Sweden in 1879 by Swedish chemist and geologist Per Teodor Cleve. The name of the element comes from the place where it was discovered, so it was called Thulium, from Thule, what the Greeks called the ancient region of Sweden in Latin, Scandinavia.

Characteristics of Thulium

Among the characteristics of thulium we find:

  • It is the least abundant element of the lanthanide group. Be careful here, promethium is found naturally on earth, although it is less abundant than thulium.
  • It is used in the nuclear industry.
  • It is a soft, malleable and ductile metal.
  • It can be cut with a knife.
  • It is a low toxic element but must be handled with care.
  • It is a good conductor of heat and electricity.
  • It has a shiny silver gray color.

Physical Properties of Thulium

  • It is an element that comes in a solid state.
  • It is a fairly stable element when exposed to air.
  • When found at temperatures below 32 K, it is a ferromagnetic element.
  • When it is at temperatures between 32 and 56 K, it is antiferromagnetic.
  • When it is greater than 56 k, it is paramagnetic.
  • It has a density of 9321 Kg/m3.
  • It has a melting point of 1818 K, which is equivalent to 15450 C.
  • It has a boiling point of 2220 K, which is equivalent to 19470 C.
  • It has an enthalpy of vaporization of 191 kJ/mol.

Atomic properties

  • It has an average radius of 175 pm, remembering that the picometer, Pm, represents one billionth of a meter.
  • Based on the Bohr radius, it has an atomic radius of 222 pm.
  • It has an electronegativity of 1.25 on the Pauling scale.
  • Oxidation index: +2, +3.
  • It has an atomic mass of 168,934.

Chemical properties

Some of the chemical properties of thulium include:

  • Thulium metal burns at a temperature of 1500 C and slowly oxidizes when exposed to air to form thulium(III) oxide:

4 Tm + 3 O2—- TmO3

  • Thulium is an electropositive metallic element that reacts with all halogens. When the temperatures are higher than 2000 C, it gives rise to vigorous reactions and otherwise, it presents slow reactions when it is at room temperature:

2 Tm (s) +3 F2 (g) —— 2 TmF3 (s) [Blanco]

2 Tm (s) +3 Cl2 (g) ——- 2 TmCl3 (s) [Amarillo]

2 Tm (s) +3 Br2 (g) ——– 2 TmBr3 (s) [Blanco]

Location in the periodic table

Electron Configuration Of Thulium We find thulium in position number 69 in the periodic table, before ytterbium and after erbium, more precisely at period 6, block f.

It is important to remember its symbology when locating it.

Thulium Applications

Thulium is a very rare and expensive element, however it does not have many applications:

  • This element can be used in portable X-ray equipment and lasers as a radiation source.
  • It can be used in ferrites, which are ceramic-magnetic materials typically used in microwave equipment.
  • Thulium has been used to create lasers, however, as mentioned earlier, its high cost has prevented the development of other possible commercial uses.

health effects

Thulium is one of the rare earth chemical elements, so it is rare to find it in nature. In fact, it only occurs in small amounts which are found in two types of minerals.

It has low toxicity; It can be found in Electron equipment and prolonged exposure can affect the liver and lungs. So far today’s study my chemistry minds, I hope you learned something new.

Electron Configuration (April 29, 2022) Electron configuration of Thulium. Retrieved from
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