63 2 · 8 · 18 · 25 · 8 · 2

Europium, Eu, element 63

Lanthanide· Period 6· f-block

Configuration [Xe]4f76s2

Atomic weight
151.964Da
Phase
solid
Density
5.24g/cm³
Melting point
1,095.15K 822 °C
Boiling point
1,802.15K 1,529 °C
Electronegativity
1.2

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. Description from mendeleev.

Back to the table
The outermost shell: the valence electronsThe inner shellsThe nucleus One bead for each electron, on the ring of its shell, counted from the nucleus out. The rings turn at their own pace; the model is Bohr's picture of the atom, which places electrons in shells but not on true orbits.

Atomic properties

5 of 5 fields have a value for europium

Atomic weight The standard atomic weight. For an element with no stable isotope, the mass of its longest-lived isotope.
151.964Da
Source: mendeleev
Electron configuration
[Xe]4f76s2
Source: mendeleev
Uncertainty of the atomic weight
0.001Da
Source: mendeleev
Electron configuration in full The electron configuration with the noble-gas core written out.
1s22s22p63s23p63d104s24p64d104f75s25p66s2
Source: Worked outfrom electron configuration
Electrons in each shell Counted from the electron configuration, from the first shell outward.
2 · 8 · 18 · 25 · 8 · 2
Source: Worked outfrom electron configuration

Screening of each subshell

Clementi's screening constants: how much of the nucleus's charge the other electrons hide from an electron in each subshell. What is left is the effective nuclear charge it feels.

SubshellScreening σEffective charge Z − σ
1s1.239161.7609
2s16.529246.4708
2p4.28258.718
3s20.131842.8682
3p19.71643.284
3d13.747249.2528
4s30.13232.868
4p31.125231.8748
4d34.059228.9408
4f38.6824.32
5s44.4118.59
5p46.44516.555
6s54.87848.1216