Sulfur

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Sulfur Quick Reference

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Notes

Symbol

S

Atomic Number

16

Atomic Weight

Rounded

32.06

for regular calculations

Standard

32.059 to 32.076

for precise calculations

Oxidation States

 6

more common with disagreement

 5

less common

 4

less common with disagreement

 3

less common

 2

less common with disagreement

 1

less common

 0

less common

-1

less common

-2

more common with disagreement

Pauling Electronegativity

2.58

Electron Configuration

Orbital Occupancy

[Ne] 3s2 3p4

[Ne] represents the closed-shell electron configuration of neon

Orbital Filling Order

[Ne] 3s2 3p4

[Ne] represents the closed-shell electron configuration of neon

Term Symbol

3P2

see expanded configuration ...

Ionization Energies

I   (1)

10.36001 eV      

II  (2)

23.33788 eV      

III (3)

34.79 eV         

IV  (4)

47.222 ± 0.012 eV

see all 16 energies ...

Electron Affinity

2.0771029 ± 0.0000010 eV

16752.966 ± 0.008 cm-1  

Density

liquid, 388.36 K

1.794 g/ml 

α-orthorhombic sulfur, solid

173 K

2.108 g/cm3

298 K

2.066 g/cm3

β-monoclinic sulfur, solid

113 K

2.088 g/cm3

298 K

2.008 g/cm3

γ-monoclinic sulfur, solid, 298 K

2.08 g/cm3 

see all 19 densities ...

Molar Volume

solid, 298 K, 1 atm

15.53 cm3/mol

Melting Point

1 bar

388.36 ± 0.02 K

α-orthorhombic sulfur

115 °C

β-monoclinic sulfur

120 °C

γ-monoclinic sulfur

109 °C

see all 13 melting points ...

Boiling Point

1 atm

717.764 K

ITS-90 second-quality, secondary reference point

α-orthorhombic sulfur, 1 atm

717.76 K 

β-monoclinic sulfur, 1 atm

717.76 K 

Thermal Conductivity

liquid, 400 K

0.132 W/(m K)

solid

300 K, polycrystalline

0.269 W/(m K)

298.2 K, polycrystalline

0.270 W/(m K)

273.2 K, polycrystalline

0.287 W/(m K)

200 K, polycrystalline

0.355 W/(m K)

amorphous sulfur, solid

300 K

0.206 W/(m K)

298.2 K

0.205 W/(m K)

273.2 K

0.200 W/(m K)

see all 50 conductivities ...

Pyykkö Covalent Radius

single bond

103 pm

double bond

 94 pm

triple bond

 95 pm

Atomic Radius

103 pm

Enthalpy of Fusion

1 atm

1.23 kJ/mol

Enthalpy of Vaporization

1 atm

9.62 kJ/mol

Quantity

Sulfur Atomic Structure

Notes

Ionization Energies

I   (1)

10.36001 eV      

II  (2)

23.33788 eV      

III (3)

34.79 eV         

IV  (4)

47.222 ± 0.012 eV

see all 16 energies ...

Electron Affinity

2.0771029 ± 0.0000010 eV

16752.966 ± 0.008 cm-1  

Electron Binding Energies

K    (1s)

2472 eV  

LI   (2s)

 230.9 eV

LII  (2p1/2)

 163.6 eV

LIII (2p3/2)

 162.5 eV

Electron Configuration

Orbital Occupancy

[Ne] 3s2 3p4

[Ne] represents the closed-shell electron configuration of neon

Orbital Filling Order

[Ne] 3s2 3p4

[Ne] represents the closed-shell electron configuration of neon

Term Symbol

3P2

see expanded configuration ...

Clementi-Raimondi Effective Nuclear Charge

1s

Orbital Exponent

15.5409

ζ

Principle Quantum Number

1

n

Effective Nuclear Charge

15.5409

Zeff = ζ × n

2s

Orbital Exponent

 5.3144

ζ

Principle Quantum Number

2

n

Effective Nuclear Charge

10.629 

Zeff = ζ × n

see all 5 effective nuclear charges ...

Screening Percentage

65.9%

Fluorescence Yields

ωK

0.080   

ωL1

0.000074

ωL2

0.00026 

ωL3

0.00026 

Coster-Kronig Yields

F12

0.32

F13

0.62

Quantity

Sulfur Physical Properties

Notes

Density

liquid, 388.36 K

1.794 g/ml 

α-orthorhombic sulfur, solid

173 K

2.108 g/cm3

298 K

2.066 g/cm3

β-monoclinic sulfur, solid

113 K

2.088 g/cm3

298 K

2.008 g/cm3

γ-monoclinic sulfur, solid, 298 K

2.08 g/cm3 

see all 19 densities ...

Molar Mass

Rounded

32.06 g/mol

for regular calculations

Standard

32.059 g/mol to 32.076 g/mol

for precise calculations

Molar Volume

solid, 298 K, 1 atm

15.53 cm3/mol

Physical Form

α-orthorhombic sulfur

yellow orthorhombic crystals

β-monoclinic sulfur

yellow monoclinic needles

Young's Modulus

α-orthorhombic sulfur

17.80 GPa

Dielectric Constant

liquid

3.5 

powder

3.6 

450 °F

3.5 

407.2 K

3.50

244 °F

3.5 

298 K

11 component of dielectric tensor, 102 Hz to 103 Hz

3.75

22 component of dielectric tensor, 102 Hz to 103 Hz

3.95

33 component of dielectric tensor, 102 Hz to 103 Hz

4.44

sublimed, 102 Hz to 103 Hz

3.69

Superconducting Transition Temperature

200 GPa

17.3 ± 0.5 K

maximum temperature

Mineralogical Hardness

2.0

Isothermal Bulk Modulus

α-orthorhombic sulfur, 300 K

17.8 GPa

Isothermal Compressibility

α-orthorhombic sulfur, 300 K

0.0562 GPa-1

Gram Atomic Volume

16 cm3

Quantity

Sulfur Atomic Interaction

Notes

Oxidation States

 6

more common with disagreement

 5

less common

 4

less common with disagreement

 3

less common

 2

less common with disagreement

 1

less common

 0

less common

-1

less common

-2

more common with disagreement

Pauling Electronegativity

2.58

Mulliken-Jaffe Electronegativity

hybridsp3

2.86

hybrid16.7% s

2.69

orbitalp

2.31

Sanderson Electronegativity

2.957

Allred-Rochow Electronegativity

2.44

Configuration Energy

electron volt units

15.31 eV

Pauling units

 2.589  

Allen Electronegativity

2.589

Allred Electronegativity

oxidation state: 2

2.58

Boyd-Edgecombe Electronegativity

2.64

Ghosh-Gupta Electronegativity

6.8379 eV

Nagle Electronegativity

2.49

Pearson Absolute Electronegativity

6.22 eV

Smith Electronegativity

oxidation state: 6

2.45

oxidation state: 4

2.5

oxidation state: -2

2.55

Chemical Hardness

4.14 eV

Cohesive Energy

per mole

275 kJ/mol    

per atom

  2.85 eV/atom

Quantity

Sulfur Thermodynamics

Notes

Melting Point

1 bar

388.36 ± 0.02 K

α-orthorhombic sulfur

115 °C

β-monoclinic sulfur

120 °C

γ-monoclinic sulfur

109 °C

see all 13 melting points ...

Boiling Point

1 atm

717.764 K

ITS-90 second-quality, secondary reference point

α-orthorhombic sulfur, 1 atm

717.76 K 

β-monoclinic sulfur, 1 atm

717.76 K 

Thermal Conductivity

liquid, 400 K

0.132 W/(m K)

solid

300 K, polycrystalline

0.269 W/(m K)

298.2 K, polycrystalline

0.270 W/(m K)

273.2 K, polycrystalline

0.287 W/(m K)

200 K, polycrystalline

0.355 W/(m K)

amorphous sulfur, solid

300 K

0.206 W/(m K)

298.2 K

0.205 W/(m K)

273.2 K

0.200 W/(m K)

see all 50 conductivities ...

Critical Point

1314 K

Vapor Pressure

444 °C

100 kPa

318 °C

10 kPa

235 °C

1 kPa

see all 16 pressures ...

Enthalpy of Fusion

1 atm

1.23 kJ/mol

Enthalpy of Vaporization

1 atm

9.62 kJ/mol

Isobaric Molar Heat Capacity

α-orthorhombic sulfur, 298.15 K, 1 bar

22.70 J/(mol K)

Isobaric Specific Heat Capacity

α-orthorhombic sulfur, 298.15 K, 1 bar

0.708 J/(g K)

Debye Temperature

Room Temperature ( 298 K )

527 K

Quantity

Sulfur Identification

Notes

CAS Number

7704-34-9

α-orthorhombic sulfur

7704-34-9

β-monoclinic sulfur

7704-34-9

DOT Number

1350

molten

2448

ICSC Number

1166

RTECS Number

WS4250000

UN Number

1350

Quantity

Sulfur Atomic Size

Notes

Atomic Radius

103 pm

Orbital Radius

81.0 pm

Pyykkö Covalent Radius

single bond

103 pm

double bond

 94 pm

triple bond

 95 pm

Cordero Covalent Radius

105 pm

Shannon-Prewitt Crystal Radius

ion charge: -2, coordination number: 6

170 pm

ion charge: +4, coordination number: 6

 51 pm

ion charge: +6

coordination number: 4

 26 pm

coordination number: 6

 43 pm

Shannon-Prewitt Effective Ionic Radius

ion charge: -2, coordination number: 6

184 pm

ion charge: +4, coordination number: 6

 37 pm

ion charge: +6

coordination number: 4

 12 pm

coordination number: 6

 29 pm

Pauling Empirical Crystal Radius

ion charge: -2

184 pm

Pauling Univalent Radius

ion charge: +1

 53 pm

ion charge: -1

219 pm

Batsanov Crystallographic Van Der Waals Radius

1.8×102 pm

Batsanov Equilibrium Van Der Waals Radius

206 pm

Bondi Van Der Waals Radius

180 pm

Pauling Van Der Waals Radius

185 pm

Slater Atomic-Ionic Radius

100 pm

Quantity

Sulfur Crystal Structure

Notes

Allotropes

allotrope

disulfur

symbol

S2

allotrope

trisulfur

symbol

S3

allotrope

tetrasulfur

symbol

S4

allotrope

cyclo-hexasulfur

alternate name

Engel's sulfur

alternate name

Aten's sulfur

alternate name

ε-sulfur

alternate name

p-sulfur

symbol

S6

allotrope category

cyclo-heptasulfur

allotrope

α–cyclo-heptasulfur

symbol

α-S7

allotrope

β–cyclo-heptasulfur

symbol

β-S7

allotrope

γ–cyclo-heptasulfur

symbol

γ-S7

allotrope

δ–cyclo-heptasulfur

symbol

δ-S7

allotrope

α-orthorhombic sulfur

symbol

α-S8

allotrope

β-monoclinic sulfur

symbol

β-S8

allotrope

γ-monoclinic sulfur

symbol

γ-S8

allotrope category

cyclo-nonasulfur

allotrope

α–cyclo-nonasulfur

symbol

α-S9

allotrope

β–cyclo-nonasulfur

symbol

β-S9

allotrope

cyclo-decasulfur

symbol

S10

allotrope

the compound S6·S10

symbol

S6·S10

allotrope

cyclo-undecasulfur

symbol

S11

allotrope

cyclo-dodecasulfur

symbol

S12

allotrope

cyclo-tridecasulfur

symbol

S13

allotrope

cyclo-tetradecasulfur

symbol

S14

allotrope

cyclo-pentadecasulfur

symbol

S15

allotrope category

cyclo-octadecasulfur

allotrope

α–cyclo-octadecasulfur

alternate name

endo-S18

symbol

α-S18

allotrope

β–cyclo-octadecasulfur

alternate name

exo-S18

symbol

β-S18

allotrope

cyclo-eicosasulfur

symbol

S20

allotrope

amorphous sulfur

alternate name

vitreous sulfur

alternate name

glassy sulfur

alternate name

plastic sulfur

allotrope

insoluble sulfur

allotrope

fibrous sulfur

symbol

Sψ

allotrope

2nd fibrous sulfur

symbol

Sψ'

allotrope

laminar sulfur

symbol

Sχ

Quantity

Sulfur History

Notes

Discovery

date of discovery

prehistory

discoverer

unknown

location of discovery

unknown

Origin of Element Name

origin

sulvere

origin description

word—Sanskrit for sulphur

Origin of Element Symbol

symbol: S

origin

sulfur

origin description

element name

U.S. Towns Named After Elements

Sulfur, Louisiana

Formerly Used or Proposed Element Names and Symbols

name

sulphur

no matching symbol specified

Quantity

Sulfur Abundances

Notes

Earth's Crust

3.50×102 ppm

Earth's Mantle

200 ppm

primitive mantle

Earth's Core

1.90%

Bulk Earth

6350 ppm

Ocean Water

928 ppm

River Water

3.7 ppm

U.S. Coal

1.8%

Human Body

140 g

based on a 70 kg "reference man"

Human Bone

500 ppm to 2400 ppm

Human Hair

42×103 ppm to 60×103 ppm

Human Kidney

9×103 ppm

Human Liver

7×103 ppm to 12×103 ppm

Human Muscle

5×103 ppm to 11×103 ppm

Human Nail

37×103 ppm

Bacteria

5.3×103 ppm

Ferns

1000 ppm

Fungi

4×103 ppm

Universe

0.00002

relative to hydrogen = 1.00000

Solar System

5.15×105

number of atoms for every 106 atoms of silicon

Sun

7.33 ± 0.11

base 10 log of the number of atoms for every 1012 atoms of hydrogen

Meteorites

7.18 ± 0.04

base 10 log of the number of atoms for every 1012 atoms of hydrogen

Halley's Comet

72 ± 23 atoms

number of atoms for every 100 atoms of magnesium

Quantity

Sulfur Nomenclature

Notes

Element Names in Other Languages

French

soufre

German

Schwefel

Italian

solfo

Spanish

azufre

Portuguese

enxofre

Anions or Anionic Substituent Groups

sulfide (general)

S•-, sulfanidyl, sulfide(•1-)

S2-, sulfanediide, sulfide(2-)

Cations or Cationic Substituent Groups

sulfur (general)

S+, sulfur(1+)

Ligands

sulfido (general)

S•-, sulfanidyl, sulfido(•1-)

S2-, sulfanediido, sulfido(2-)

Heteroatomic Anion

sulfate

'a' Term—Substitutive Nomenclature

thia

'y' Term—Chains and Rings Nomenclature

sulfy

References    (Click the button next to a value above to see complete citation information for that entry)

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