Platinum (Pt): electron configuration, atomic mass and facts
Platinum (Pt) is element 78 of the periodic table, a transition metal in period 6, group 10. Its electron configuration is [Xe] 4f14 5d9 6s1, with electrons arranged in shells 2, 8, 18, 32, 17, 1, and its standard atomic weight is 195.08 u.
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| Symbol | Pt |
|---|---|
| Atomic number | 78 |
| Atomic mass | 195.08 u |
| Category | Transition metal |
| Group | 10 |
| Period | 6 |
| Block | d-block |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d9 6s1 |
| Noble-gas shorthand | [Xe] 4f14 5d9 6s1 |
| Electrons per shell | 2, 8, 18, 32, 17, 1 |
| Electronegativity (Pauling) | 2.28 |
| State at 20 °C | solid |
Where is Platinum on the periodic table?
Platinum is in period 6, group 10, in the d-block. The period number matches its 6 electron shells, and the block names the subshell its last electrons fill. In the same group, Palladium sits directly above it and Darmstadtium sits directly below it. Elements in the same column of the d-block often have similar chemistry.
How to work out the electron configuration of Platinum
Put 78 electrons into subshells in order of rising energy, filling each before starting the next: 1s² (2), 2s² (4), 2p⁶ (10), 3s² (12), 3p⁶ (18), 4s² (20), 3d¹⁰ (30), 4p⁶ (36), 5s² (38), 4d¹⁰ (48), 5p⁶ (54), 6s² (56), 4f¹⁴ (70), 5d⁸ (78). Platinum is one of the exceptions to this filling order: experiments show its ground state is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s¹ 4f¹⁴ 5d⁹ rather than 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d⁸, because the neighbouring subshells are so close in energy. In shorthand, [Xe] stands for the 54 electrons of xenon, giving [Xe] 4f¹⁴ 5d⁹ 6s¹.
How electronegative is Platinum?
Platinum has a Pauling electronegativity of 2.28, ranking 15 of the 100 elements with a known value (fluorine is highest at 3.98). That is in the middle of the range.
Frequently asked questions
What is the electron configuration of Platinum?
The electron configuration of Platinum (Pt) is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d9 6s1. In noble-gas shorthand it is written [Xe] 4f14 5d9 6s1.
How many electrons does Platinum have in each shell?
Platinum has 78 electrons arranged in shells as 2, 8, 18, 32, 17, 1.
What is the atomic mass of Platinum?
The standard atomic weight of Platinum is 195.08 u, so one mole of Platinum atoms has a mass of about 195.08 g.
Is Platinum a metal?
Yes. Platinum is a transition metal.
Explore nearby elements
More transition metals: Tungsten, Rhenium, Osmium, Iridium, Gold, Mercury. See all elements on the periodic table.