Periodic Table

Sulfur

Nonmetal

Quick Facts about Sulfur

P
  • solid- state of matter at room temperature
  • Stable- has at least one stable isotope
  • +6, +4, -2- common oxidation states in compounds
  • ORC- crystal structure, atomic arrangement in solid form
Cl

Sulfur (S) is element 16 on the periodic table. Atomic mass of S: 32.0600 u. S is in period 3, group 16. Melting point of S: 388.36 K.Density of S: 2.07 g/cm³.

Why Sulfur Matters

The element that smells like rotten eggs and makes rubber bounce

In Your Home

  • Matches (sulfur tips)
  • Rubber products (vulcanized rubber)
  • Wine preservative (sulfites)
  • Some medicines and supplements

Industry Uses

ChemicalSulfuric acid is #1 industrial chemical worldwide
AgricultureFertilizers and pesticides
PetroleumRemoved from fuels (desulfurization)
RubberVulcanization makes rubber durable

In Your Body

✓ Essential for life

Essential in amino acids (cysteine, methionine), vitamins (biotin, thiamine), and proteins. Disulfide bonds give hair and skin their structure.

Safety: Elemental sulfur is low toxicity. Hydrogen sulfide (H2S) is deadly toxic (rotten egg smell). Sulfur dioxide causes respiratory irritation.

Discovery of Sulfur

Discovered by Known to the ancients.,

Name origin: Latin: sulphur (brimstone).

History & Events

2000 BCE
Ancient Use
Ancient Egyptians used sulfur to bleach cotton. Homer mentioned 'brimstone' fumigation.
1839
Vulcanization
Charles Goodyear discovered sulfur vulcanization, revolutionizing rubber industry
1909
Frasch Process
Herman Frasch's hot water extraction made sulfur mining economical

About Sulfur

Yellow, nonmetallic element belonging to group 16 of the periodic table. It is an essential element in living organisms, needed in the amino acids cysteine and methionine, and hence in many proteins. Absorbed by plants from the soil as sulphate ion.

Atomic Properties of S

Atomic Number of S
16
Atomic Mass of S
32.0600 u
Electron Configuration
[Ne] 3s2 3p4
Electronegativity
2.58
Block
p-block
Group
16
Period
3

Physical Properties of S

Phase (STP)
solid
Melting Point of S
388.36 K
Boiling Point of S
717.80 K
Density of S
2.0700 g/cm3

Thermal Properties

Heat of Fusion
1.23 kJ/mol
Heat of Vaporization
10.50 kJ/mol
Specific Heat
0.71 J/g·K
Molar Heat Capacity
22.70 J/mol·K
Thermal Conductivity
0.27 W/m·K

Atomic Radii

Calculated
100 pm
Covalent
103 pm
Van der Waals
180 pm
Metallic
104 pm

Common Misconceptions

Wrong:Sulfur always smells bad.
Correct:Pure sulfur is nearly odorless. The 'rotten egg' smell is hydrogen sulfide (H2S), not elemental sulfur.
Wrong:Sulfites in wine are dangerous.
Correct:Sulfites are safe for most people. Only ~1% have sensitivity. Wine naturally contains sulfites anyway.
Wrong:Brimstone is a different substance.
Correct:Brimstone is just the ancient name for sulfur—from 'burning stone.'

Allotropes of Sulfur

Sulfur exists in 4 different structural forms (allotropes), each with unique properties.

Rhombic Sulfur (S8)

Most stable form at room temperature, yellow crystals

Structure:Crown-shaped S8 rings in orthorhombic crystal
Properties:Stable below 95.5°C, density 2.07 g/cm3
Uses:Vulcanization, fertilizers, fungicides

Monoclinic Sulfur (β-S8)

Needle-like yellow crystals

Structure:S8 rings in monoclinic crystal arrangement
Properties:Stable between 95.5°C and 119°C

Plastic Sulfur

Rubber-like form made by quenching molten sulfur

Structure:Long helical chains
Properties:Elastic, converts back to rhombic over time

Other Cyclic Forms

S6, S7, S9, S10, S11, S12, S18, S20 rings

Structure:Various ring sizes
Properties:Less stable than S8, some synthesized in lab

Isotopes of Sulfur

Sulfur has 4 naturally occurring isotopes, plus 1 notable radioactive isotope.

IsotopeAtomic Mass (u)AbundanceHalf-LifeDecay Mode
3216S (S-32)Sulfur-32 isotope31.9720711794.99%
3316S (S-33)Sulfur-33 isotope32.971458910.7500%
3416S (S-34)Sulfur-34 isotope33.9678674.250%
3516S (S-35)Sulfur-35 isotope34.969032310%87.37 daysβ⁻
3616S (S-36)Sulfur-36 isotope35.967080710.0100%

Data source: NIH PubChem (aggregated from IUPAC, NIST)

Isotope Applications

Isotopes of Sulfur have important real-world applications in science and industry.

Geochronology & Dating

35S has a half-life of 87 days, which is an ideal duration for use as a conservative tracer in atmospheric processes. 35SO2 gas is produced as a natural product of argon exposure to cosmic rays in the atmosphere. Because 35SO2 gas is present in the atmosphere and then precipitates and falls as moisture in the form of 35SO42-, 35S can act as a tracer to study air mass transport dynamics and atmospheric oxidation capacity [147]. Analyses of 35S in lake water and precipitation can also be used as a tracer to monitor contributions of sulfur that originated in precipitation to surface waters. If a water tests positive for the isotope 35S, it provides evidence that the water had been affected by recent (<~1 year) precipitation [148], [149], [150]. 35S is used in direct labeling of elemental sulfur or sulfate sources to trace the fate of sulfur in fertilizers [142].

Abundance

Earth's Crust
350.0 mg/kg
Seawater
905.0 mg/L

Uses

Used in matches, gunpowder, medicines, rubber and pesticides, dyes and insecticides. Also for making sulfuric acid (H2SO4).

Sources

Found in pure form and in ores like cinnabar, galena, sphalerite and stibnite. Pure form is obtained from undergound deposits by the Frasch process.

Geochemistry

Goldschmidt
chalcophile
Geochemical Class
semi-volatile

Test Your Knowledge

Loading quiz...