---
title: "Tin (Sn): Atomic Mass, Electron Configuration & Properties"
url: https://www.moldraw.com/elements/tin.html
description: "Tin (Sn), element 50: atomic mass 118.71, electron configuration [Kr] 4d¹⁰ 5s² 5p², group 14, period 5, p-block post-transition metal. Melting and boiling point, density, electronegativity and shells."
lang: en
publisher: Scidart Academy
generated: 2026-11-03
---
50Sn118.71

# Tin (Sn) – element 50

Tin is a chemical element with the symbol **Sn** and atomic number **50**. It is a post-transition metal in group 14, period 5 of the periodic table (p-block), and is a solid at room temperature.

Tin (Sn) has atomic number 50, atomic mass 118.71 u and electron configuration [Kr] 4d10 5s2 5p2.

[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)

## Tin facts

| Symbol | Sn |
| --- | --- |
| Atomic number | 50 |
| Atomic mass | 118.71 u (g/mol) |
| Category | post-transition metal |
| Group | group 14 |
| Period | 5 |
| Block | p-block |
| Phase at 20 °C | Solid |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p2 |
| Noble-gas notation | [Kr] 4d10 5s2 5p2 |
| Electrons per shell | 2, 8, 18, 18, 4 |
| Valence electrons | 4 |

## Bohr model and shells

Tin has 50 electrons in 5 shells: 2, 8, 18, 18, 4. 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 | 505.08 K (231.9 °C) |
| --- | --- |
| Boiling point | 2875 K (2601.8 °C) |
| Density | 7.365 g/cm³ |
| Electronegativity (Pauling) | 1.96 |
| Electron affinity | 107.298 kJ/mol |
| Ionization energies | 708.6, 1411.8, 2943 kJ/mol (1st, 2nd, 3rd) |
| Molar heat capacity | 27.112 J/(mol·K) |
| Discovered by | unknown, before 3500 BC |

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 Sn.

## Position in the periodic table

Tap any element to open its page.

## Frequently asked questions

### What is the atomic mass of tin?

The atomic mass of tin is 118.71 u, so one mole of tin atoms weighs 118.71 g.

### What is the electron configuration of tin?

Tin has 50 electrons: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p², or [Kr] 4d¹⁰ 5s² 5p² in noble-gas notation. Electrons per shell: 2, 8, 18, 18, 4.

### How many valence electrons does tin have?

Tin has 4 valence electrons (group 14).

### Is tin a metal?

Yes. Tin is a post-transition metal.

### Where is tin on the periodic table?

Tin is in group 14, period 5, in the p-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.