78 2 · 8 · 18 · 32 · 17 · 1

Platinum, Pt, element 78

Transition metal· Period 6· Group 10· d-block

Configuration [Xe]4f¹⁴5d⁹6s¹

Atomic weight: 195.084Da
Phase: solid
Density: 21.5g/cm³
Melting point: 2,041.35K 1,768.2 °C
Boiling point: 4,098.15K 3,825 °C
Electronegativity: 2.2

Attractive greyish-white metal. When pure, it is malleable and ductile. Does not oxidize in air, insoluble in hydrochloric and nitric acid. Corroded by halogens, cyandies, sulphur and alkalis. Hydrogen and Oxygen react explosively in the presence of platinumpy. There are six stable isotopes and three radioisotopes, the most stable being Pt-193 with a half-life of 60 years. Platinum is used in jewelry, laboratory equipment, electrical contacts, dentistry, and anti-pollution devices in cars. PtCl2(NH3)2 is used to treat some forms of cancer. Platinum-Cobalt alloys have magnetic properties. It is also used in the definition of the Standard Hydrogen Electrode. Discovered by Antonio de Ulloa in South America in 1735. The name comes from the Spanish word platina which means silver. Platinum metal is generally not a health concern due to its unreactivity, however platinum compounds should be considered highly toxic. 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 platinum

Atomic weight The standard atomic weight. For an element with no stable isotope, the mass of its longest-lived isotope.: 195.084Da; Source: mendeleev
Electron configuration: [Xe]4f¹⁴5d⁹6s¹; Source: mendeleev
Uncertainty of the atomic weight: 0.009Da; Source: mendeleev
Electron configuration in full The electron configuration with the noble-gas core written out.: 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰4f¹⁴5s²5p⁶5d⁹6s¹; Source: Worked outfrom electron configuration
Electrons in each shell Counted from the electron configuration, from the first shell outward.: 2 · 8 · 18 · 32 · 17 · 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.

Subshell	Screening σ	Effective charge Z − σ
1s	1.506	76.494
2s	20.3702	57.6298
2p	4.4746	73.5254
3s	23.0157	54.9843
3p	22.1139	55.8861
3d	13.5027	64.4973
4s	34.3612	43.6388
4p	35.2696	42.7304
4d	37.37	40.63
4f	38.494	39.506
5s	51.412	26.588
5p	53.5805	24.4195
5d	58.5925	19.4075
6s	67.2486	10.7514