Tin (Sn)

Below about 13 °C ordinary white tin slowly converts into grey tin, a crumbly powder — a transformation called tin pest that has been blamed, probably too neatly, for disintegrating buttons on Napoleon's army in Russia and for the failure of Scott's fuel cans in Antarctica. Tin has ten stable isotopes, more than any other element, a consequence of 50 being a "magic number" of protons. Float glass, invented by Pilkington in 1959, works because molten glass poured onto a bath of liquid tin spreads perfectly flat and does not mix with it, which is why window glass no longer has to be ground and polished.

Properties

Atomic number

50

Symbol

Sn

Standard atomic weight

118.71 u

Category

Post-transition metal

Group

14

Period

5

Block

p-block

Electron configuration

[Kr] 5s² 4d¹⁰ 5p²

Electrons per shell

2, 8, 18, 18, 4

Melting point

505.08 K — 231.9 °C — 449.5 °F

Boiling point

2,875 K — 2601.8 °C — 4715.3 °F

Density

7.287 g/cm³

Electronegativity

1.96 (Pauling)

Oxidation states

+4, +2

Discovered

Known since antiquity

Electron configuration

Full

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p²

Noble gas shorthand

[Kr] 5s² 4d¹⁰ 5p²

Shells

K: 2 · L: 8 · M: 18 · N: 18 · O: 4

What it is used for

• Solder for electronics and plumbing
• The tin coating inside a steel food can
• Bronze, which is copper and tin
• Float glass manufacture, where molten glass is poured onto liquid tin
• Organotin stabilisers in PVC

Neighbours in the table

Group 14

Elements in the same group share their outer electron count, which is why they behave similarly in reactions. Tin sits in group 14 with carbon, silicon, germanium, lead, flerovium.