Sulfur
Element 16 · Nonmetal
Sulfur announces itself by smell: the rotten-egg stink of hydrogen sulfide near volcanoes and hot springs. Ancient peoples called it brimstone and burned it in rituals; today it is an industrial giant. Sulfuric acid, made from sulfur, is produced by the hundreds of millions of tons each year for fertilizers, batteries, and metal refining. Biology needs sulfur too — the amino acids cysteine and methionine use it to fold proteins into shape, and it gives onions, garlic, and skunk spray their punch. Yellow sulfur deposits mark where it erupts from volcanic depths.
Key facts
| Atomic number | 16 |
|---|---|
| Atomic weight | 32.06 |
| Category | Nonmetal |
| Group / Period | 16 / 3 |
| Block | p |
| Electron configuration | 1s2 2s2 2p6 3s2 3p4 |
| Common oxidation states | +6, +4, +2, -2 |
| State at STP | Solid |
| Electronegativity | 2.58 |
| Atomic radius | 88 pm |
| Density | 2.07 g/cm³ |
| Melting point | 115.21 °C |
| Boiling point | 444.6 °C |
Occurrence
Sulfur collects around volcanoes and in underground deposits, and hides in sulfide ores like pyrite and in natural gas as hydrogen sulfide. The human body holds about 140 grams, mostly in proteins.
Applications
Sulfuric acid manufacturing
Vulcanizing rubber
Fungicides and pesticides
Winemaking (sulfite preservatives)
Gunpowder (historic)
Common compounds
- Sulfuric acid (H2SO4)
- Hydrogen sulfide (H2S)
- Sulfur dioxide (SO2)
- Iron pyrite (FeS2)
A nation's sulfuric acid output is a classic yardstick of its chemical industry — chemists call it the 'king of chemicals'.
Data source: IUPAC standard atomic weights 2021