Europium: the essentials
Europium ignites in air at about 150 to 180°C. Europium is about as hard as lead and is quite ductile. It is the most reactive of the rare earth metals, quickly oxidising in air. It resembles calcium in its reaction with water. It is used in television screens to produce a red colour.
This sample is from The Elements Collection, an attractive and safely packaged collection of the 92 naturally occurring elements that is available for sale.
Europium: historical information
The discovery of europium is generally credited to Eug/ne-Antole Demarcay, who separated the earth in reasonably pure form in 1901 from a material containing largely samarium. Pure europium metal was not isolated until much more recently.
Europium around us Read more »
Europium has no biological role.
Europium is never found in nature as the free element. Europium is found in the ores monazite sand [(Ce, La, etc.)PO4] and bastn°site [(Ce, La, etc.)(CO3)F], ores containing small amounts of all the rare earth metals. It is difficult to separate from other rare earth elements. Europium has been identified spectroscopically in the sun and some stars.
|Location||ppb by weight||ppb by atoms||Links|
|Human||(no data) ppb by weight||(no data) atoms relative to C = 1000000|
Physical properties Read more »
Heat properties Read more »
- Melting point: 1099 [826 °C (1519 °F)] K
- Boiling point: 1800 [1527 °C (2781 °F)] K
- Enthalpy of fusion: 9.2 kJ mol-1
Crystal structure Read more »
The solid state structure of europium is: bcc (body-centred cubic).
Europium: orbital properties Read more »
Europium atoms have 63 electrons and the shell structure is 18.104.22.168.8.2. The ground state electronic configuration of neutral Europium is [Xe].4f7.6s2 and the term symbol of Europium is 8S7/2.
- Pauling electronegativity: (no data) (Pauling units)
- First ionisation energy: 547.1 kJ mol‑1
- Second ionisation energy: 1085 kJ mol‑1
Isolation: europium metal is available commercially so it is not normally necessary to make it in the laboratory, which is just as well as it is difficult to isolate as the pure metal. This is largely because of the way it is found in nature. The lanthanoids are found in nature in a number of minerals. The most important are xenotime, monazite, and bastnaesite. The first two are orthophosphate minerals LnPO4 (Ln deonotes a mixture of all the lanthanoids except promethium which is vanishingly rare) and the third is a fluoride carbonate LnCO3F. Lanthanoids with even atomic numbers are more common. The most comon lanthanoids in these minerals are, in order, cerium, lanthanum, neodymium, and praseodymium. Monazite also contains thorium and ytrrium which makes handling difficult since thorium and its decomposition products are radioactive.
For many purposes it is not particularly necessary to separate the metals, but if separation into individual metals is required, the process is complex. Initially, the metals are extracted as salts from the ores by extraction with sulphuric acid (H2SO4), hydrochloric acid (HCl), and sodium hydroxide (NaOH). Modern purification techniques for these lanthanoid salt mixtures are ingenious and involve selective complexation techniques, solvent extractions, and ion exchange chromatography.
Pure europium is available through the electrolysis of a mixture of molten EuCl3 and NaCl (or CaCl2) in a graphite cell which acts as cathode using graphite as anode. The other product is chlorine gas.
Europium isotopes Read more »
Europium has two stable isotopes and both are used for the production of radioisotopes. Eu-151 is used for the production of Eu-152 which is used as a reference source in gammaspectroscopy. Eu-153 can be used for the production of high specific activity Sm-153 via fast neutron irradiation.
|151Eu||150.919702 (8)||47.81 (3)||5/2||3.4718|
|153Eu||152.921225 (4)||52.19 (3)||5/2||1.5331|