Tin (Sn)
Post-transition metal
Tin gave its name to an age of civilisation: alloyed with copper it makes bronze. Corrosion-resistant and non-toxic, it coats steel food cans and, melted, floats the glass for nearly every window in the world.
Position on the periodic table
Atomic properties
| Atomic number | 50 |
|---|---|
| Atomic mass | 118.711 amu |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p2 |
| Noble gas shorthand | [Kr] 4d10 5s2 5p2 |
| Electrons per shell | 2, 8, 18, 18, 4 |
| Valence electrons (outer shell) | 4 |
| Common oxidation states | +4, +2 |
| Electronegativity (Pauling) | 1.96 |
| Covalent radius (approx.) | 139 pm |
| First ionization energy | 708.6 kJ/mol |
| Electron affinity | 107.3 kJ/mol |
Physical properties
| State at 25 °C | Solid |
|---|---|
| Density | 7.365 g/cm³ |
| Melting point | 231.93 °C (505.08 K) |
| Boiling point | 2601.8 °C (2875 K) |
| Appearance | silvery-white (beta, β) or gray (alpha, α) |
| Radioactive | No |
| Origin | Occurs naturally |
Electron configuration of tin
Tin's ground-state electron configuration is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p2, usually shortened to [Kr] 4d10 5s2 5p2. Its electrons occupy 5 shells (2, 8, 18, 18, 4), placing it in period 5 of the p-block. The 4 outer-shell electrons drive its bonding behaviour. Explore it interactively in the electron configuration calculator.
Uses of tin
- Solder for electronics
- Tin-plating steel cans
- Bronze and pewter alloys
- Float glass production
Biological role: No confirmed essential role.
Occurrence: Mined mainly as cassiterite (SnO₂).
Common compounds of tin
SnO2
Tin(IV) oxide
SnCl2
Tin(II) chloride
History and discovery
Discovered: Known since ancient times — unknown, before 3500 BC. Name origin: From Old English tin; the symbol Sn comes from Latin stannum.
Bronze-age smiths alloyed tin with copper from about 3000 BCE, transforming tools, weapons and trade.
Safety notes
Metallic tin is safe (hence food cans); some organotin compounds are highly toxic and restricted.
Educational context only — always follow your school's laboratory rules and never handle chemicals without proper supervision. See our disclaimer.
Practice questions
Quick practice: Tin
1. What is the chemical symbol of Tin?
2. What is the atomic number of Tin?
3. Which category does Tin belong to?
4. What is the state of Tin at room temperature?
5. Which period of the periodic table is Tin in?
Tin FAQs
What is the atomic number of tin?
Tin's atomic number is 50 — every tin atom has 50 protons in its nucleus.
What is the symbol for tin?
Sn. From Old English tin; the symbol Sn comes from Latin stannum.
Is tin a metal, nonmetal, or metalloid?
Tin is classified as a post-transition metal.
What state is tin at room temperature?
At about 25 °C, tin is a solid. It melts at 231.93 °C.
How many valence electrons does tin have?
Tin has 4 electrons in its outer shell (shell pattern: 2, 8, 18, 18, 4).
What is tin used for?
Key uses include: solder for electronics; tin-plating steel cans; bronze and pewter alloys.
Related elements
Keep working with this element
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