Europium (Eu)
Soft silvery metallic element belonging to the lanthanoids. Eu-151 and Eu-153 are the only two stable isotopes, both of which are Neutron absorbers. Discovered in 1889 by Sir William Crookes.
| Atomic Number | 63 |
|---|---|
| Atomic Weight | 151.964 |
| Mass Number | 153 |
| Group | |
|---|---|
| Period | 6 |
| Block | f |
| Protons | 63 p+ |
|---|---|
| Neutrons | 90 n0 |
| Electrons | 63 e- |
Properties
| Atomic Radius | 185 pm
|
|---|---|
| Atomic Volume | 28.9 cm³/mol
|
| Covalent Radius | 168 pm
|
| Metallic Radius | |
| Ionic Radius | 117 pm
|
| Crystal Radius | 131 pm
|
| Van der Waals radius |
235 pm
|
| Density | 5.24 g/cm³
|
| Boiling Point | 1,870 K
|
| Melting Point | 1,095 K
|
| Electrons per shell | 2, 8, 18, 25, 8, 2 |
| Electronegativity | |
| Electrophilicity | 1.11045482541 eV/particle
|
| Proton Affinity | |
| Electron Affinity | 0.864 eV/particle
|
| Ionization Potential | 5.670385 eV/particle
|
| Heat of Vaporization | 176 kJ/mol
|
| Heat of Fusion | |
| Heat of Formation | 177.4 kJ/mol
|
| Molar Heat Capacity | 27.66 J/(mol K)
|
| Specific Heat Capacity | 0.182 J/(g⋅K)
|
| Thermal Conductivity | 13.9 W/(m K)
|
| Gas Basicity | |
| Dipole Polarizability | 184 a₀
|
| C6 Dispersion Coefficient | |
| Oxidation States | 2, 3 |
| Color | Silver
|
| Crystal Structure | Body Centered Cubic (BCC) |
| Lattice Constant | 4.61 Å
|
| Bulk Modulus | |
| Electrical Resistivity | |
| Electron Configuration | [Xe] 4f7 6s2 |
| Magnetic Ordering | |
| Magnetic Susceptibility | |
| Phase | Solid |
| Poisson Ratio | |
| Shear Modulus | |
| Young's Modulus | |
| Allotropes | |
| Alternate Names | |
| Adiabatic Index | |
| Appearance | |
| Electric Conductivity | |
| Critical Pressure | |
| Critical Temperature | |
| Curie Point | |
| Electrical | |
| Hardness | |
| Magnetic Susceptibility | |
| Magnetic | |
| Neel Point | |
| Neutron Cross Section | |
| Neutron Mass Absorption | |
| Gas Phase | |
| Quantum Numbers | |
| Refractive Index | |
| Space Group | |
| Speed of Sound | |
| Superconducting Point | |
| Thermal Expansion | |
| Valence Electrons | |
| Classification | |
| Category | Lanthanides, Lanthanides |
| CAS Group | |
| IUPAC Group | |
| Glawe Number | 17 |
| Mendeleev Number | 25 |
| Pettifor Number | 18 |
| Geochemical Class | rare earth & related |
| Goldschmidt Class | litophile |
| Radioactivity | |
| Radioactive | No |
| Decay Mode | |
| Half-Life | |
| Lifetime | |
| Abundance | |
| Abundance in Earth's crust | 2 mg/kg
|
| Abundance in Oceans | 0.00000013 mg/L
|
| Abundance in Human Body | |
| Abundance in Meteor | |
| Abundance in Sun | |
| Abundance in Universe | 5×10-8% |
Isotopes of Europium
Stable Isotopes
151Eu 153Eu
Unstable Isotopes
130Eu 131Eu 132Eu 133Eu 134Eu 135Eu 136Eu 137Eu 138Eu 139Eu 140Eu 141Eu 142Eu 143Eu 144Eu 145Eu 146Eu 147Eu 148Eu 149Eu 150Eu 152Eu 154Eu 155Eu 156Eu 157Eu 158Eu 159Eu 160Eu 161Eu 162Eu 163Eu 164Eu 165Eu 166Eu 167Eu
History
Europium was first found by Paul Émile Lecoq de Boisbaudran in 1890. In 1896, French chemist Eugène-Antole Demarçay identified spectroscopic lines in ‘samarium' caused by europium. He successfully isolated europium in 1901 using repeated crystallizations of samarium magnesium nitrate. Europium was named after Europe
| Discoverers | Eugène Demarçay |
|---|---|
| Discovery Location | France |
| Discovery Year | 1901 |
| Name Origin | Named for the continent of Europe. |
Europium is considered to be mildly toxic
Europium is the most reactive rare earth element
Uses
Europium is used in the manufacture of fluorescent glass. It is also used in the anti-counterfeiting phosphors in Euro banknotes. Europium-doped plastic has been used as a laser material. Europium isotopes are good neutron absorbers and are used in nuclear reactor control rods. Used with yttrium oxide to make red phosphors for color televisions.
Sources
Obtained from monazite sand, which is a mixture of phosphates of calcium, thorium, cerium, and most other rare earths.