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Oxygen Quick Reference

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Notes

Symbol

O

Atomic Number

8

Atomic Weight

Rounded

15.999

for regular calculations

Standard

15.99903 to 15.99977

for precise calculations

Oxidation States

 2

less common

 1

less common

 0

less common

-1

less common

-2

more common

Pauling Electronegativity

3.44

Electron Configuration

Orbital Occupancy

[He] 2s2 2p4

[He] represents the closed-shell electron configuration of helium

Orbital Filling Order

[He] 2s2 2p4

[He] represents the closed-shell electron configuration of helium

Term Symbol

3P2

see expanded configuration ...

Ionization Energies

I   (1)

13.61805 eV

II  (2)

35.1211 eV 

III (3)

54.9355 eV 

IV  (4)

77.41353 eV

see all 8 energies ...

Electron Affinity

1.4611120 ± 0.0000027 eV

11784.664 ± 0.022 cm-1  

Density

gas

400.0 K, 1 atm

0.9749 g/L

300.0 K

1 atm

1.301 g/L 

1 bar

1.284 g/L 

25 °C, 1 atm

1.3080 g/L

280.0 K, 1 atm

1.394 g/L 

273.15 K, 1 atm

1.428 g/L 

200.0 K, 1 atm

1.956 g/L 

see all 51 densities ...

Molar Volume

gas, 273.15 K, 1 atm

22.4134 L/mol

Melting Point

molecular oxygen

10 bar

54.47 K

2.0 bar

54.38 K

1.5 bar

54.38 K

1 atm

54.37 K

1 bar

54.37 K

0.8 bar

54.37 K

0.6 bar

54.37 K

ozone, 1 atm

80.15 K

Boiling Point

molecular oxygen

2.0 bar

 97.24 K 

1 atm

 90.197 K

1 bar

 90.06 K 

ozone, 1 atm

161.80 K 

see all 8 boiling points ...

Thermal Conductivity

gas

400 K, 1 atm

0.0342 W/(m K) 

300 K, 1 atm

0.02674 W/(m K)

290 K, 1 atm

0.02592 W/(m K)

280 K, 1 atm

0.02509 W/(m K)

270 K, 1 atm

0.02424 W/(m K)

200 K, 1 atm

0.01824 W/(m K)

see all 48 conductivities ...

Pyykkö Covalent Radius

single bond

63 pm

double bond

57 pm

triple bond

53 pm

Atomic Radius

74 pm

Enthalpy of Fusion

1 atm

0.444 kJ/mol

Enthalpy of Vaporization

1 atm

6.82 kJ/mol

Quantity

Oxygen Atomic Structure

Notes

Ionization Energies

I   (1)

13.61805 eV

II  (2)

35.1211 eV 

III (3)

54.9355 eV 

IV  (4)

77.41353 eV

see all 8 energies ...

Electron Affinity

1.4611120 ± 0.0000027 eV

11784.664 ± 0.022 cm-1  

Electron Binding Energies

K  (1s)

543.1 eV

LI (2s)

 41.6 eV

Electron Configuration

Orbital Occupancy

[He] 2s2 2p4

[He] represents the closed-shell electron configuration of helium

Orbital Filling Order

[He] 2s2 2p4

[He] represents the closed-shell electron configuration of helium

Term Symbol

3P2

see expanded configuration ...

Clementi-Raimondi Effective Nuclear Charge

1s

Orbital Exponent

7.6579

ζ

Principle Quantum Number

1

n

Effective Nuclear Charge

7.6579

Zeff = ζ × n

2s

Orbital Exponent

2.2458

ζ

Principle Quantum Number

2

n

Effective Nuclear Charge

4.4916

Zeff = ζ × n

2p

Orbital Exponent

2.2266

ζ

Principle Quantum Number

2

n

Effective Nuclear Charge

4.4532

Zeff = ζ × n

Screening Percentage

43.1%

Fluorescence Yields

ωK

0.0069

Quantity

Oxygen Physical Properties

Notes

Density

gas

400.0 K, 1 atm

0.9749 g/L

300.0 K

1 atm

1.301 g/L 

1 bar

1.284 g/L 

25 °C, 1 atm

1.3080 g/L

280.0 K, 1 atm

1.394 g/L 

273.15 K, 1 atm

1.428 g/L 

200.0 K, 1 atm

1.956 g/L 

see all 51 densities ...

Molar Mass

Rounded

15.999 g/mol

for regular calculations

Standard

15.99903 g/mol to 15.99977 g/mol

for precise calculations

Molar Volume

gas, 273.15 K, 1 atm

22.4134 L/mol

Physical Form

molecular oxygen

colorless gas

ozone

blue gas

Speed of Sound

gas

300 K

1 atm

329 m/s

1 bar

329 m/s

295 K, 1 atm

327 m/s

285 K, 1 atm

321 m/s

275 K, 1 atm

315 m/s

270 K, 1 atm

313 m/s

200 K, 1 atm

269 m/s

see all 52 speeds of sound ...

Dielectric Constant

68 °F

1.00

-315 °F

1.51

54.48 K

1.57

ozone, 90.2 K

4.75

Superconducting Transition Temperature

100 GPa

0.6 K

maximum temperature

Gram Atomic Volume

11 cm3

Quantity

Oxygen Atomic Interaction

Notes

Oxidation States

 2

less common

 1

less common

 0

less common

-1

less common

-2

more common

Pauling Electronegativity

3.44

Mulliken-Jaffe Electronegativity

hybridsp2

3.94

hybridsp3

3.68

hybrid16.7% s

3.41

orbitalp

2.82

Sanderson Electronegativity

3.654

Allred-Rochow Electronegativity

3.50

Configuration Energy

electron volt units

21.36 eV

Pauling units

 3.610  

Allen Electronegativity

3.610

Allred Electronegativity

oxidation state: 2

3.44

Boyd-Edgecombe Electronegativity

3.62

Ghosh-Gupta Electronegativity

8.7861 eV

Nagle Electronegativity

3.62

Pearson Absolute Electronegativity

7.54 eV

Smith Electronegativity

oxidation state: -2

3.65

Chemical Hardness

6.08 eV

Cohesive Energy

per mole

251 kJ/mol    

per atom

  2.60 eV/atom

Quantity

Oxygen Thermodynamics

Notes

Melting Point

molecular oxygen

10 bar

54.47 K

2.0 bar

54.38 K

1.5 bar

54.38 K

1 atm

54.37 K

1 bar

54.37 K

0.8 bar

54.37 K

0.6 bar

54.37 K

ozone, 1 atm

80.15 K

Boiling Point

molecular oxygen

2.0 bar

 97.24 K 

1 atm

 90.197 K

1 bar

 90.06 K 

ozone, 1 atm

161.80 K 

see all 8 boiling points ...

Thermal Conductivity

gas

400 K, 1 atm

0.0342 W/(m K) 

300 K, 1 atm

0.02674 W/(m K)

290 K, 1 atm

0.02592 W/(m K)

280 K, 1 atm

0.02509 W/(m K)

270 K, 1 atm

0.02424 W/(m K)

200 K, 1 atm

0.01824 W/(m K)

see all 48 conductivities ...

Triple Point

temperature

54.3584 K

ITS-90 fixed point

pressure

0.152 kPa

Critical Point

temperature

154.581 K

pressure

5.043 MPa

Vapor Pressure

molecular oxygen

100 K

254 kPa

-200.5 °C

10 kPa

-211.9 °C

1 kPa

ozone

-111.5 °C

100 kPa

-139.7 °C

10 kPa

-158 °C

1 kPa

see all 36 pressures ...

Enthalpy of Fusion

1 atm

0.444 kJ/mol

Enthalpy of Vaporization

1 atm

6.82 kJ/mol

Isobaric Molar Heat Capacity

gas

300 K

1 atm

29.44 J/(mol K)

1 bar

29.43 J/(mol K)

295 K, 1 atm

29.41 J/(mol K)

285 K, 1 atm

29.37 J/(mol K)

275 K, 1 atm

29.34 J/(mol K)

270 K, 1 atm

29.32 J/(mol K)

200 K, 1 atm

29.27 J/(mol K)

see all 50 capacities ...

Isobaric Specific Heat Capacity

298.15 K, 1 bar

0.918 J/(g K)

Isochoric Molar Heat Capacity

gas

300 K

1 atm

21.08 J/(mol K)

1 bar

21.08 J/(mol K)

295 K, 1 atm

21.05 J/(mol K)

285 K, 1 atm

21.01 J/(mol K)

275 K, 1 atm

20.97 J/(mol K)

270 K, 1 atm

20.96 J/(mol K)

200 K, 1 atm

20.84 J/(mol K)

see all 50 capacities ...

Quantity

Oxygen Identification

Notes

CAS Number

molecular oxygen

7782-44-7

ozone

10028-15-6

DOT Number

1072

compressed

1072

refrigerated liquid (cryogenic liquid)

1073

ICSC Number

gas

0138

liquefied

0880

RTECS Number

RS2060000

ozone

RS8225000

UN Number

gas

1072

liquefied

1073

Quantity

Oxygen Atomic Size

Notes

Atomic Radius

74 pm

Orbital Radius

45.0 pm

Pyykkö Covalent Radius

single bond

63 pm

double bond

57 pm

triple bond

53 pm

Cordero Covalent Radius

66 pm

Shannon-Prewitt Crystal Radius

ion charge: -2

coordination number: 2

121 pm

coordination number: 3

122 pm

coordination number: 4

124 pm

coordination number: 6

126 pm

coordination number: 8

128 pm

Shannon-Prewitt Effective Ionic Radius

ion charge: -2

coordination number: 2

135 pm

coordination number: 3

136 pm

coordination number: 4

138 pm

coordination number: 6

140 pm

coordination number: 8

142 pm

Pauling Empirical Crystal Radius

ion charge: -2

140 pm

Pauling Univalent Radius

ion charge: +1

 22 pm

ion charge: -1

176 pm

Batsanov Crystallographic Van Der Waals Radius

155 pm

Batsanov Equilibrium Van Der Waals Radius

171 pm

Bondi Van Der Waals Radius

152 pm

Pauling Van Der Waals Radius

140 pm

Slater Atomic-Ionic Radius

60 pm

Quantity

Oxygen Crystal Structure

Notes

Allotropes

allotrope

α-oxygen

symbol

α-O2

allotrope

β-oxygen

symbol

β-O2

allotrope

γ-oxygen

symbol

γ-O2

allotrope

orange oxygen

alternate name

δ-oxygen

symbol

δ-O2

allotrope

red oxygen

alternate name

ε-oxygen

symbol

ε-O2

allotrope

metallic oxygen

alternate name

ζ-oxygen

symbol

ζ-O2

allotrope

molecular oxygen

alternate name

oxygen

alternate name

dioxygen

symbol

O2

allotrope

ozone

alternate name

trioxygen

symbol

O3

Quantity

Oxygen History

Notes

Discovery

shared discovery

date of discovery

1774

discoverer

Joseph Priestley

birth

March 13, 1733

death

February 6, 1804

location of discovery

Wiltshire, England

shared discovery

date of discovery

1771–1772

discoverer

Carl Wilhelm Scheele

birth

December 9 (or 19), 1742

death

May 21, 1786

location of discovery

Uppsala, Sweden

Origin of Element Name

origin

oksys gen

origin description

property—Greek for acidic producing

Origin of Element Symbol

symbol: O

origin

oxygen

origin description

element name

Quantity

Oxygen Abundances

Notes

Earth's Crust

4.61×105 ppm

Earth's Mantle

44.33%

primitive mantle

Bulk Earth

29.7%

Earth's Atmosphere

20.95%

O2

Ocean Water

8.56×105 ppm

River Water

8.8×105 ppm

U.S. Coal

16%

Human Body

43 kg

based on a 70 kg "reference man"

Human Bone

285×103 ppm

Human Hair

245×103 ppm

Human Kidney

160×103 ppm

Human Liver

160×103 ppm

Human Muscle

160×103 ppm

Human Nail

255×103 ppm

Bacteria

230×103 ppm

Ferns

430×103 ppm

Fungi

340×103 ppm

Universe

0.00085

relative to hydrogen = 1.00000

Solar System

2.38×107

number of atoms for every 106 atoms of silicon

Sun

8.83 ± 0.06

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

Moon

Terrae

61.1 ± 0.9 %

Maria

60.3 ± 0.4 %

Average

60.9%

Meteorites

8.43 ± 0.04

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

Halley's Comet

890 ± 110 atoms

number of atoms for every 100 atoms of magnesium

Quantity

Oxygen Nomenclature

Notes

Element Names in Other Languages

French

oxygène

German

Sauerstoff

Italian

ossigeno

Spanish

oxígeno

Portuguese

oxigénio

Anions or Anionic Substituent Groups

oxide (general)

O•-, oxidanidyl, oxide(•1-)

O2-, oxide(2-)

Cations or Cationic Substituent Groups

oxygen (general)

O•+, oxygen(•1+)

Ligands

O2-, oxido

Heteroatomic Anion

oxygenate

'a' Term—Substitutive Nomenclature

oxa

'y' Term—Chains and Rings Nomenclature

oxy

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

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