Neptunium is silvery, tarnishes when exposed to air and occurs in three allotropic forms and it normally exhibits five oxidation states, ranging from +3 to +7. It is radioactive, pyrophoric, and can accumulate in bones, which makes the handling of neptunium dangerous. The most stable isotope of neptunium, neptunium-237, is a by-product of nuclear reactors and plutonium production.

Neptunium is silvery, tarnishes when exposed to air and occurs in three allotropic forms and it normally exhibits five oxidation states, ranging from +3 to +7. It is radioactive, pyrophoric, and can accumulate in bones, which makes the handling of neptunium dangerous. The most stable isotope of neptunium, neptunium-237, is a by-product of nuclear reactors and plutonium production.

Neptunium is silvery, tarnishes when exposed to air and occurs in three allotropic forms and it normally exhibits five oxidation states, ranging from +3 to +7. It is radioactive, pyrophoric, and can accumulate in bones, which makes the handling of neptunium dangerous. The most stable isotope of neptunium, neptunium-237, is a by-product of nuclear reactors and plutonium production.

Neptunium is silvery, tarnishes when exposed to air and occurs in three allotropic forms and it normally exhibits five oxidation states, ranging from +3 to +7. It is radioactive, pyrophoric, and can accumulate in bones, which makes the handling of neptunium dangerous. The most stable isotope of neptunium, neptunium-237, is a by-product of nuclear reactors and plutonium production.

Neptunium is silvery, tarnishes when exposed to air and occurs in three allotropic forms and it normally exhibits five oxidation states, ranging from +3 to +7. It is radioactive, pyrophoric, and can accumulate in bones, which makes the handling of neptunium dangerous. The most stable isotope of neptunium, neptunium-237, is a by-product of nuclear reactors and plutonium production.

---

1940 by Edwin McMillan and Philip H. Abelson, USA.

1940 by Edwin McMillan and Philip H. Abelson, USA.

1940 by Edwin McMillan and Philip H. Abelson, USA.

1940 by Edwin McMillan and Philip H. Abelson, USA.

1940 by Edwin McMillan and Philip H. Abelson, USA.

DISCOVERY

DISCOVERY

DISCOVERY

DISCOVERY

DISCOVERY

---

From the name Neptune, the planet.

From the name Neptune, the planet.

From the name Neptune, the planet.

From the name Neptune, the planet.

From the name Neptune, the planet.

ETYMOLOGY

ETYMOLOGY

ETYMOLOGY

ETYMOLOGY

ETYMOLOGY

---

---

Neptunium

Neptunium

Neptunium

Neptunium

Neptunium

---

Element

Element

Element

Element

Element

---

Np

Np

Np

Np

Np

---

Symbol

Symbol

Symbol

Symbol

Symbol

---

---

---

93

93

93

93

93

---

Atomic Number

Atomic Number

Atomic Number

Atomic Number

Atomic Number

---

Actinide

Actinide

Actinide

Actinide

Actinide

---

Classification

Classification

Classification

Classification

Classification

---

7439-99-8

7439-99-8

7439-99-8

7439-99-8

7439-99-8

---

CAS Number

CAS Number

CAS Number

CAS Number

CAS Number

---

Silver

Silver

Silver

Silver

Silver

---

Elemental Colour

Elemental Colour

Elemental Colour

Elemental Colour

Elemental Colour

---

-

-

-

-

-

---

Refractive Index

Refractive Index

Refractive Index

Refractive Index

Refractive Index

---

-

-

-

-

-

---

Poisson Ratio

Poisson Ratio

Poisson Ratio

Poisson Ratio

Poisson Ratio

---

11.567 cm³

11.567 cm³

11.567 cm³

11.567 cm³

11.567 cm³

---

Molar Volume

Molar Volume

Molar Volume

Molar Volume

Molar Volume

---

-

-

-

-

-

---

Brinell Hardness

Brinell Hardness

Brinell Hardness

Brinell Hardness

Brinell Hardness

---

-

-

-

-

-

---

Mohs Hardness

Mohs Hardness

Mohs Hardness

Mohs Hardness

Mohs Hardness

---

-

-

-

-

-

---

Vickers Hardness

Vickers Hardness

Vickers Hardness

Vickers Hardness

Vickers Hardness

---

-

-

-

-

-

---

Speed of Sound

Speed of Sound

Speed of Sound

Speed of Sound

Speed of Sound

---

-

-

-

-

-

---

Bulk Modulus

Bulk Modulus

Bulk Modulus

Bulk Modulus

Bulk Modulus

---

-

-

-

-

-

---

Shear Modulus

Shear Modulus

Shear Modulus

Shear Modulus

Shear Modulus

---

-

-

-

-

-

---

Young Modulus

Young Modulus

Young Modulus

Young Modulus

Young Modulus

---

---

---

Allotropes

Allotropes

Allotropes

Allotropes

Allotropes

---

---

---

917.15 K, 644.00 °C

917.15 K, 644.00 °C

917.15 K, 644.00 °C

917.15 K, 644.00 °C

644.00 °C

---

Melting Point

Melting Point

Melting Point

Melting Point

Melting Point

---

4,273.15 K, 4,000.00 °C

4,273.15 K, 4,000.00 °C

4,273.15 K, 4,000.00 °C

4,273.15 K, 4,000.00 °C

4,000.00 °C

---

Boiling Point

Boiling Point

Boiling Point

Boiling Point

Boiling Point

---

-

-

-

-

-

---

Automatic Ignition

Automatic Ignition

Automatic Ignition

Automatic Ignition

Automatic Ignition

---

-

-

-

-

-

---

Flashpoint

Flashpoint

Flashpoint

Flashpoint

Flashpoint

---

-

-

-

-

-

---

Critical Temperature

Critical Temperature

Critical Temperature

Critical Temperature

Critical Temperature

---

-

-

-

-

-

---

Critical Pressure

Critical Pressure

Critical Pressure

Critical Pressure

Critical Pressure

---

6.000'000 W/(m K)

6.000'000 W/(m K)

6.000'000 W/(m K)

6.000'000 W/(m K)

6.000'000 W/(m K)

---

Thermal Conductivity

Thermal Conductivity

Thermal Conductivity

Thermal Conductivity

Thermal Conductivity

---

-

-

-

-

-

---

Thermal Expansion

Thermal Expansion

Thermal Expansion

Thermal Expansion

Thermal Expansion

---

-

-

-

-

-

---

Specific Heat

Specific Heat

Specific Heat

Specific Heat

Specific Heat

---

10.000 kJ/mol

10.000 kJ/mol

10.000 kJ/mol

10.000 kJ/mol

10.000 kJ/mol

---

Heat Fusion

Heat Fusion

Heat Fusion

Heat Fusion

Heat Fusion

---

335.000 kJ/mol

335.000 kJ/mol

335.000 kJ/mol

335.000 kJ/mol

335.000 kJ/mol

---

Heat Vaporisation

Heat Vaporisation

Heat Vaporisation

Heat Vaporisation

Heat Vaporisation

---

-

-

-

-

-

---

Heat Combustion

Heat Combustion

Heat Combustion

Heat Combustion

Heat Combustion

---

-

-

-

-

-

---

Curie Point

Curie Point

Curie Point

Curie Point

Curie Point

---

-

-

-

-

-

---

Neel Point

Neel Point

Neel Point

Neel Point

Neel Point

---

-

-

-

-

-

---

Adiabatic Index

Adiabatic Index

Adiabatic Index

Adiabatic Index

Adiabatic Index

---

Solid

Solid

Solid

Solid

Solid

---

Phase

Phase

Phase

Phase

Phase

Conductor

Conductor

Conductor

Conductor

Conductor

---

Electrical Type

Electrical Type

Electrical Type

Electrical Type

Electrical Type

---

830.00k S/m

830.00k S/m

830.00k S/m

830.00k S/m

830.00k S/m

---

Conductivity

Conductivity

Conductivity

Conductivity

Conductivity

---

1.20μ Ω.m

1.20μ Ω.m

1.20μ Ω.m

1.20μ Ω.m

1.20μ Ω.m

---

Resistivity

Resistivity

Resistivity

Resistivity

Resistivity

---

-

-

-

-

-

---

Superconducting Point

Superconducting Point

Superconducting Point

Superconducting Point

Superconducting Point

---

-

-

-

-

-

---

Magnetic Type

Magnetic Type

Magnetic Type

Magnetic Type

Magnetic Type

---

-

-

-

-

-

---

Mass Susceptibility

Mass Susceptibility

Mass Susceptibility

Mass Susceptibility

Mass Susceptibility

---

-

-

-

-

-

---

Molar Susceptibility

Molar Susceptibility

Molar Susceptibility

Molar Susceptibility

Molar Susceptibility

---

-

-

-

-

-

---

Volume Susceptibility

Volume Susceptibility

Volume Susceptibility

Volume Susceptibility

Volume Susceptibility

Material Composition

Material Composition

Material Composition

Material Composition

Material Composition

---

-

-

-

-

-

---

Universe

Universe

Universe

Universe

Universe

---

-

-

-

-

-

---

Meteorites

Meteorites

Meteorites

Meteorites

Meteorites

---

-

-

-

-

-

---

Sun

Sun

Sun

Sun

Sun

---

-

-

-

-

-

---

Earth Crust

Earth Crust

Earth Crust

Earth Crust

Earth Crust

---

-

-

-

-

-

---

Oceans

Oceans

Oceans

Oceans

Oceans

---

-

-

-

-

-

---

Humans

Humans

Humans

Humans

Humans

236.547'371'8

236.547'371'8

236.547'371'8

236.547'371'8

236.547'371'8

---

Atomic Weight

Atomic Weight

Atomic Weight

Atomic Weight

Atomic Weight

---

140 pm

140 pm

140 pm

140 pm

140 pm

---

Atomic Radius

Atomic Radius

Atomic Radius

Atomic Radius

Atomic Radius

---

171 pm

171 pm

171 pm

171 pm

171 pm

---

Covalent Radius Single Bond

Covalent Radius Single Bond

Covalent Radius Single Bond

Covalent Radius Single Bond

Covalent Radius Single Bond

---

136 pm

136 pm

136 pm

136 pm

136 pm

---

Covalent Radius Double Bond

Covalent Radius Double Bond

Covalent Radius Double Bond

Covalent Radius Double Bond

Covalent Radius Double Bond

---

116 pm

116 pm

116 pm

116 pm

116 pm

---

Covalent Radius Triple Bond

Covalent Radius Triple Bond

Covalent Radius Triple Bond

Covalent Radius Triple Bond

Covalent Radius Triple Bond

---

221 pm

221 pm

221 pm

221 pm

221 pm

---

Van der Waals Radius

Van der Waals Radius

Van der Waals Radius

Van der Waals Radius

Van der Waals Radius

---

[Rn]7s²5f⁴6d¹

[Rn]7s²5f⁴6d¹

[Rn]7s²5f⁴6d¹

[Rn]7s²5f⁴6d¹

[Rn]7s²5f⁴6d¹

---

Electron Configuration

Electron Configuration

Electron Configuration

Electron Configuration

Electron Configuration

---

Orthorhombic, Primitive

Orthorhombic, Primitive

Orthorhombic, Primitive

Orthorhombic, Primitive

Orthorhombic, Primitive

---

Crystal Structure

Crystal Structure

Crystal Structure

Crystal Structure

Crystal Structure

---

20.450'00 g/cm³

20.450'00 g/cm³

20.450'00 g/cm³

20.450'00 g/cm³

20.450'00 g/cm³

---

Density as Solid

Density as Solid

Density as Solid

Density as Solid

Density as Solid

---

-

-

-

-

-

---

Density as Liquid

Density as Liquid

Density as Liquid

Density as Liquid

Density as Liquid

---

-

-

-

-

-

---

Density as Gas

Density as Gas

Density as Gas

Density as Gas

Density as Gas

---

Pnma

Pnma

Pnma

Pnma

Pnma

---

Space Group Name

Space Group Name

Space Group Name

Space Group Name

Space Group Name

---

62

62

62

62

62

---

Space Group Number

Space Group Number

Space Group Number

Space Group Number

Space Group Number

---

π/2, π/2 & π/2

π/2, π/2 & π/2

π/2, π/2 & π/2

π/2, π/2 & π/2

π/2, π/2 & π/2

---

Lattice Angles

Lattice Angles

Lattice Angles

Lattice Angles

Lattice Angles

---

666.3, 472.3 & 488.7 pm

666.3, 472.3 & 488.7 pm

666.3, 472.3 & 488.7 pm

666.3, 472.3 & 488.7 pm

666.3, 472.3 & 488.7 pm

---

Lattice Constants

Lattice Constants

Lattice Constants

Lattice Constants

Lattice Constants

6

6

6

6

6

---

Valence

Valence

Valence

Valence

Valence

---

1.36

1.36

1.36

1.36

1.36

---

Electronegativity

Electronegativity

Electronegativity

Electronegativity

Electronegativity

---

-

-

-

-

-

---

Electron Affinity

Electron Affinity

Electron Affinity

Electron Affinity

Electron Affinity

---

---

---

Ionisation Energy

Ionisation Energy

Ionisation Energy

Ionisation Energy

Ionisation Energy

---

---

---

2.15 x 10⁶ years

2.15 x 10⁶ years

2.15 x 10⁶ years

2.15 x 10⁶ years

2.15 x 10⁶ years

---

Half Life

Half Life

Half Life

Half Life

Half Life

---

3.10 x 10⁶ years

3.10 x 10⁶ years

3.10 x 10⁶ years

3.10 x 10⁶ years

3.10 x 10⁶ years

---

Lifetime

Lifetime

Lifetime

Lifetime

Lifetime

---

6d¹ = 6, 2, -2, +1/2

6d¹ = 6, 2, -2, +1/2

6d¹ = 6, 2, -2, +1/2

6d¹ = 6, 2, -2, +1/2

6d¹ = 6, 2, -2, +1/2

---

Quantum Numbers

Quantum Numbers

Quantum Numbers

Quantum Numbers

Quantum Numbers

---

14.500'00 b σ_s

14.500'00 b σ_s

14.500'00 b σ_s

14.500'00 b σ_s

14.500'00 b σ_s

---

Neutron Cross Section

Neutron Cross Section

Neutron Cross Section

Neutron Cross Section

Neutron Cross Section

---

175.900'00 b σ_a

175.900'00 b σ_a

175.900'00 b σ_a

175.900'00 b σ_a

175.900'00 b σ_a

---

Neutron Mass Absorption

Neutron Mass Absorption

Neutron Mass Absorption

Neutron Mass Absorption

Neutron Mass Absorption

---

---

---

Stable Isotopes

Stable Isotopes

Stable Isotopes

Stable Isotopes

Stable Isotopes

---

NONE

NONE

NONE

NONE

NONE

---

---

---

Unstable Isotopes

Unstable Isotopes

Unstable Isotopes

Unstable Isotopes

Unstable Isotopes

---

---

---

---

Isotopes Overview

Isotopes Overview

Isotopes Overview

Isotopes Overview

Isotopes Overview

---

---

---