Uranium

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Uranium Quick Reference

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Notes

Symbol

U

Atomic Number

92

Atomic Weight

Rounded

238.0

for regular calculations

Standard

238.02891 ± 0.00003

for precise calculations

Oxidation States

6

more common

5

less common

4

less common

3

less common

2

unverified

Pauling Electronegativity

1.38

Electron Configuration

Orbital Occupancy

[Rn] 5f3 6d1 7s2

[Rn] represents the closed-shell electron configuration of radon

Orbital Filling Order

[Rn] 7s2 5f3 6d1

[Rn] represents the closed-shell electron configuration of radon

Term Symbol

5L6

see expanded configuration ...

Ionization Energies

I  (1)

 6.1941 eV

II (2)

10.6 eV   

Density

liquid, 1408.15 K

17.907 g/ml 

solid, 25 °C

19.100 g/cm3

Molar Volume

solid, 298 K, 1 atm

12.49 cm3/mol

Melting Point

1407 ± 2 K

Boiling Point

1 atm

4404.15 K

Thermal Conductivity

solid

400 K, polycrystalline

29.6 W/(m K)

300 K, polycrystalline

27.6 W/(m K)

298.2 K, polycrystalline

27.5 W/(m K)

273.2 K, polycrystalline

27.0 W/(m K)

200 K, polycrystalline

25.1 W/(m K)

see all 44 conductivities ...

Pyykkö Covalent Radius

single bond

170 pm

double bond

134 pm

triple bond

118 pm

Atomic Radius

139 pm

Enthalpy of Fusion

1 atm

15.5 kJ/mol

Enthalpy of Vaporization

1 atm

422.6 kJ/mol

Quantity

Uranium Atomic Structure

Notes

Ionization Energies

I  (1)

 6.1941 eV

II (2)

10.6 eV   

Electron Binding Energies

K    (1s)

115606 eV  

LI   (2s)

 21757 eV  

LII  (2p1/2)

 20948 eV  

LIII (2p3/2)

 17166 eV  

see all 24 energies ...

Electron Configuration

Orbital Occupancy

[Rn] 5f3 6d1 7s2

[Rn] represents the closed-shell electron configuration of radon

Orbital Filling Order

[Rn] 7s2 5f3 6d1

[Rn] represents the closed-shell electron configuration of radon

Term Symbol

5L6

see expanded configuration ...

Fluorescence Yields

ωK

0.970

ωL1

0.168

ωL2

0.506

ωL3

0.444

Coster-Kronig Yields

F12

0.035

F13

0.62 

F23

0.14 

Quantity

Uranium Physical Properties

Notes

Density

liquid, 1408.15 K

17.907 g/ml 

solid, 25 °C

19.100 g/cm3

Molar Mass

Rounded

238.0 g/mol

for regular calculations

Standard

238.02891 ± 0.00003 g/mol

for precise calculations

Molar Volume

solid, 298 K, 1 atm

12.49 cm3/mol

Physical Form

silvery-white orthorhombic crystals

Linear Thermal Expansion Coefficient

25 °C

13.9×10-6 K-1

Speed of Sound

solid, 293 K, annealed

3030 m/s to 3280 m/s

calculated value

Specific Gravity

68 °F, water at 4 °C (39.2 °F)

19.05 

13 °C, water at 4 °C (39.2 °F)

18.485

Young's Modulus

177 GPa

Poisson's Ratio

0.250

Electrical Resistivity

solid, 295 K

25.7×10-8 Ohm m

Contact Potential

4.32 eV

Photoelectric Work Function

3.63 eV

Thermionic Work Function

3.27 eV

Superconducting Transition Temperature

α-uranium, 1.2 GPa

2.4 K

maximum temperature

β-uranium, ambient pressure

0.8 K

Mineralogical Hardness

β-uranium

6.0

Vickers Hardness

293 K

1960 MN/m2

573 K

 785 MN/m2

see all 9 hardnesses ...

Isothermal Bulk Modulus

300 K

98.7 GPa

Isothermal Compressibility

300 K

0.0101 GPa-1

Gram Atomic Volume

13 cm3

Quantity

Uranium Atomic Interaction

Notes

Oxidation States

6

more common

5

less common

4

less common

3

less common

2

unverified

Pauling Electronegativity

1.38

Allred-Rochow Electronegativity

1.22

Allred Electronegativity

oxidation state: 2

1.38

Nagle Electronegativity

1.06

Smith Electronegativity

oxidation state: 6

1.75

oxidation state: 4

1.45

oxidation state: 3

1.35

Cohesive Energy

per mole

536 kJ/mol    

per atom

  5.55 eV/atom

Quantity

Uranium Thermodynamics

Notes

Melting Point

1407 ± 2 K

Boiling Point

1 atm

4404.15 K

Thermal Conductivity

solid

400 K, polycrystalline

29.6 W/(m K)

300 K, polycrystalline

27.6 W/(m K)

298.2 K, polycrystalline

27.5 W/(m K)

273.2 K, polycrystalline

27.0 W/(m K)

200 K, polycrystalline

25.1 W/(m K)

see all 44 conductivities ...

Critical Point

12500 K

Vapor Pressure

4129 °C

100 kPa

3454 °C

10 kPa

2961 °C

1 kPa

2586 °C

100 Pa

2291 °C

10 Pa

2052 °C

1 Pa

Enthalpy of Fusion

1 atm

15.5 kJ/mol

Enthalpy of Vaporization

1 atm

422.6 kJ/mol

Isobaric Molar Heat Capacity

crystalline solid, 298.15 K, 1 bar

27.665 J/(mol K)

Isobaric Specific Heat Capacity

298.15 K, 1 bar

0.116 J/(g K)

Electronic Heat Capacity Coefficient

9.14 mJ/(mol K2)

Debye Temperature

Low Temperature Limit ( 0 K )

248 K

Room Temperature ( 298 K )

300 K

Quantity

Uranium Identification

Notes

CAS Number

7440-61-1

DOT Number

metal, pyrophoric

2979

RTECS Number

YR3490000

Quantity

Uranium Atomic Size

Notes

Atomic Radius

139 pm

Orbital Radius

177.5 pm

Pyykkö Covalent Radius

single bond

170 pm

double bond

134 pm

triple bond

118 pm

Cordero Covalent Radius

196 pm

Shannon-Prewitt Crystal Radius

ion charge: +3, coordination number: 6

116.5 pm

ion charge: +4

coordination number: 6

103 pm  

coordination number: 7

109 pm  

coordination number: 8

114 pm  

coordination number: 9

119 pm  

coordination number: 12

131 pm  

ion charge: +5

coordination number: 6

 90 pm  

coordination number: 7

 98 pm  

ion charge: +6

coordination number: 2

 59 pm  

coordination number: 4

 66 pm  

coordination number: 6

 87 pm  

coordination number: 7

 95 pm  

coordination number: 8

100 pm  

Shannon-Prewitt Effective Ionic Radius

ion charge: +3, coordination number: 6

102.5 pm

ion charge: +4

coordination number: 6

 89 pm  

coordination number: 7

 95 pm  

coordination number: 8

100 pm  

coordination number: 9

105 pm  

coordination number: 12

117 pm  

ion charge: +5

coordination number: 6

 76 pm  

coordination number: 7

 84 pm  

ion charge: +6

coordination number: 2

 45 pm  

coordination number: 4

 52 pm  

coordination number: 6

 73 pm  

coordination number: 7

 81 pm  

coordination number: 8

 86 pm  

Pauling Empirical Crystal Radius

ion charge: +4

 97 pm

ion charge: +3

111 pm

Batsanov Crystallographic Van Der Waals Radius

2.3×102 pm

Batsanov Equilibrium Van Der Waals Radius

265 pm

Bondi Van Der Waals Radius

186 pm

Slater Atomic-Ionic Radius

175 pm

Quantity

Uranium Crystal Structure

Notes

Allotropes

allotrope

α-uranium

symbol

αU

allotrope

β-uranium

symbol

βU

allotrope

γ-uranium

symbol

γU

Nearest Neighbor Distance

300 K, 1 atm

275 pm

Atomic Concentration

300 K, 1 atm

4.80×1022 cm-3

Quantity

Uranium History

Notes

Discovery

date of discovery

1789

discoverer

Martin Heinrich Klaproth

birth

December 1, 1743

death

January 1, 1817

location of discovery

Berlin, Germany

Origin of Element Name

origin

Uranus

origin description

celestial body—Planet

Origin of Element Symbol

symbol: U

origin

uranium

origin description

element name

Quantity

Uranium Abundances

Notes

Earth's Crust

2.7 ppm

Earth's Mantle

21.8 ppb

primitive mantle

Bulk Earth

0.015 ppm

Ocean Water

0.0033 ppm

Metalliferous Ocean Sediment

Basal

4.2 ppm

Ridge

22 ppm

River Water

4×10-5 ppm

U.S. Coal

2.1 ppm

Human Body

0.1 mg

based on a 70 kg "reference man"

Human Bone

0.00016 ppm to 0.07 ppm

Human Hair

0.00013 ppm

Human Kidney

0.009 ppm to 0.024 ppm

Human Liver

0.003 ppm

Human Muscle

0.0009 ppm

Fungi

<0.03 ppm

Solar System

0.0090

number of atoms for every 106 atoms of silicon

Sun

<-0.47

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

Meteorites

-0.52 ± 0.04

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

Quantity

Uranium Nomenclature

Notes

Element Names in Other Languages

French

uranium

German

Uran

Italian

uranio

Spanish

uranio

Portuguese

urânio

Anions or Anionic Substituent Groups

uranide

Cations or Cationic Substituent Groups

uranium

Ligands

uranido

Heteroatomic Anion

uranate

'a' Term—Substitutive Nomenclature

urana

'y' Term—Chains and Rings Nomenclature

urany

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