Tin
Element 50 · Post-Transition Metal
Tin is one of humanity's oldest metals — alloying it with copper created bronze and launched the Bronze Age. Today it is the backbone of electronics solder, joining components on circuit boards, and its corrosion resistance makes it the standard coating inside steel food cans ('tin cans'). Tin is unusual for existing in two solid forms at everyday temperatures: shiny, malleable white tin and brittle gray tin, with white tin slowly converting to the gray powdery form in prolonged cold. Its chemistry centers on the +2 and +4 oxidation states, seen in compounds from tin(II) chloride to the tin dioxide coatings on energy-efficient windows.
Key facts
| Atomic number | 50 |
|---|---|
| Atomic weight | 118.71 |
| Category | Post-Transition Metal |
| Group / Period | 14 / 5 |
| Block | p |
| Electron configuration | [Kr] 4d10 5s2 5p2 |
| Common oxidation states | +4, +2 |
| State at STP | Solid |
| Electronegativity | 1.96 |
| Atomic radius | 145 pm (empirical) |
| Density | 7.31 g/cm³ |
| Melting point | 231.93 °C |
| Boiling point | 2602 °C |
Occurrence
Tin is mined mainly from the mineral cassiterite (tin dioxide), with major deposits in Southeast Asia, China, and South America. Humans have smelted tin for over 5,000 years.
Applications
Solder for electronics
Tin plating on steel food cans
Bronze and pewter alloys
Float glass manufacturing
Common compounds
- Tin dioxide
- Tin(II) chloride
- Tin(IV) chloride
Tin suffers from 'tin pest': below 13.2 °C, shiny white tin slowly crumbles into a gray powder — a real problem for organ pipes in cold churches.
Data source: IUPAC standard atomic weights 2021; NIST physical property data