44 2 · 8 · 18 · 15 · 1

Ruthenium, Ru, element 44

Transition metal· Period 5· Group 8· d-block

Configuration [Kr]4d75s1

Atomic weight
101.07Da
Phase
solid
Density
12.1g/cm³
Melting point
2,606.15K 2,333 °C
Boiling point
4,420.15K 4,147 °C
Electronegativity
2.2

Hard white metallic transition element. Found with platinum, used as a catalyst in some platinum alloys. Dissolves in fused alkalis, and is not attacked by acids. Reacts with halogens and oxygen at high temperatures. Isolated in 1844 by K.K. Klaus. 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 ruthenium

Atomic weight The standard atomic weight. For an element with no stable isotope, the mass of its longest-lived isotope.
101.07Da
Source: mendeleev
Electron configuration
[Kr]4d75s1
Source: mendeleev
Uncertainty of the atomic weight
0.02Da
Source: mendeleev
Electron configuration in full The electron configuration with the noble-gas core written out.
1s22s22p63s23p63d104s24p64d75s1
Source: Worked outfrom electron configuration
Electrons in each shell Counted from the electron configuration, from the first shell outward.
2 · 8 · 18 · 15 · 1
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
1s0.907743.0923
2s11.620232.3798
2p4.049239.9508
3s16.398827.6012
3p16.778927.2211
3d14.641129.3589
4s26.34417.656
4p27.565216.4348
4d31.187212.8128
5s37.51556.4845