---
title: "Platinum (Pt): Atomic Mass, Electron Configuration & Properties"
url: https://www.moldraw.com/elements/platinum.html
description: "Platinum (Pt), element 78: atomic mass 195.08, electron configuration [Xe] 4f¹⁴ 5d⁹ 6s¹, group 10, period 6, d-block transition metal. Melting and boiling point, density, electronegativity and shells."
lang: en
publisher: Scidart Academy
generated: 2026-11-03
---
78Pt195.08

# Platinum (Pt) – element 78

Platinum is a chemical element with the symbol **Pt** and atomic number **78**. It is a transition metal in group 10, period 6 of the periodic table (d-block), and is a solid at room temperature.

Platinum (Pt) has atomic number 78, atomic mass 195.08 u and electron configuration [Xe] 4f14 5d9 6s1.

[Download periodic table PDF](https://www.moldraw.com/printables/periodic-table.pdf)[Open interactive periodic table](https://www.moldraw.com/tools/free-chem-tools/interactive-periodic-table.html)

## Platinum facts

| Symbol | Pt |
| --- | --- |
| Atomic number | 78 |
| Atomic mass | 195.08 u (g/mol) |
| Category | transition metal |
| Group | group 10 |
| Period | 6 |
| Block | d-block |
| Phase at 20 °C | Solid |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s1 4f14 5d9 |
| Noble-gas notation | [Xe] 4f14 5d9 6s1 |
| Electrons per shell | 2, 8, 18, 32, 17, 1 |

## Bohr model and shells

Platinum has 78 electrons in 6 shells: 2, 8, 18, 32, 17, 1. Full configuration and noble-gas notation are in the table; work out any element or ion with the [electron configuration calculator](https://www.moldraw.com/tools/free-chem-tools/electron-configuration-calculator.html).

## Physical and atomic properties

| Melting point | 2041.4 K (1768.2 °C) |
| --- | --- |
| Boiling point | 4098 K (3824.8 °C) |
| Density | 21.45 g/cm³ |
| Electronegativity (Pauling) | 2.28 |
| Electron affinity | 205.041 kJ/mol |
| Ionization energies | 870, 1791 kJ/mol (1st, 2nd) |
| Molar heat capacity | 25.86 J/(mol·K) |
| Discovered by | Antonio de Ulloa |

Use the atomic mass in the [molar mass calculator](https://www.moldraw.com/tools/free-chem-tools/molar-mass-calculator.html) for any formula containing Pt.

## Position in the periodic table

Tap any element to open its page.

## Frequently asked questions

### What is the atomic mass of platinum?

The atomic mass of platinum is 195.08 u, so one mole of platinum atoms weighs 195.08 g.

### What is the electron configuration of platinum?

Platinum has 78 electrons: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s¹ 4f¹⁴ 5d⁹, or [Xe] 4f¹⁴ 5d⁹ 6s¹ in noble-gas notation. Electrons per shell: 2, 8, 18, 32, 17, 1.

### Is platinum a metal?

Yes. Platinum is a transition metal.

### Where is platinum on the periodic table?

Platinum is in group 10, period 6, in the d-block.

Data: [Periodic-Table-JSON](https://github.com/Bowserinator/Periodic-Table-JSON) (CC BY-SA 3.0); standard atomic weights from IUPAC (abridged). Values in brackets are the mass number of the longest-lived isotope.