Neptunium Element Properties, Rare Earth, Actinides Group, Periodic Table of the Elements
Neptunium
|
Neptunium Element Properties |
 | | General |
| Name | Neptunium |
| Symbol | Np |
| Number | 93 |
| Group Number | NA |
| Group | Rare Earth, Actinides |
| Block | f |
| Density | 20.45 g/cm3 |
| Atomic Weight | 237.0482 g/mol |
| Atomic Volume | 11.62 cm3/mol |
| Discover | 1940 |
|
| States |
| State | Solid |
| Melting Point | 910 K |
| Boiling Point | 4273 K |
| Triple Point | Nil |
| Critical Point | Nil |
| Heat of Fusion | 3.20 kJ/mol |
| Heat of Vaporization | 336 kJ/mol |
|
| Energies |
| First Ionization Energy | 597 kJ/mole |
| Second Ionization Energy | Nil |
| Third Ionization Energy | Nil |
| Electronegativity | 1.3 |
| Electron Affinity | Nil |
| Specific Heat | 0.12 J/gK |
| Heat Atomization | Nil |
|
| Oxidation and Electrons |
| Shells | 2,8,18,32,23,8,2 |
| Electron Configuration | [Rn] 5f4 6d1 7s2 |
| Minimum Oxidation Number | 0 |
| Maximum Oxidation Number | 7 |
| Minimum Common Oxidation Number | 0 |
| Maximum Common Oxidation Number | 5 |
|
| Appearance and Characteristics |
| Crystal Structure | 3 forms: orthorhombic, tetragonal and cubic |
| Characteristics | Radioactive |
| Color | silvery |
| Uses | Nil |
| Hardness | Nil |
| Toxicity | None |
|
| Reactions |
| Reaction with Air | None |
| Reaction with 6M HCl | None |
| Reaction with 15M HNO3 | None |
| Reaction with 6M NaOH | None |
|
| Other Forms |
| Number of Isotopes | 0 |
| Hydride | NpH2 NpH3 |
| Oxide | NpO NpO2 Np2O5 |
| Chloride | NpCl3 NpCl4 |
|
| Radius |
| Atomic Radius | 155 pm |
| Ionic Radius (1+ ion) | Nil |
| Ionic Radius (1- ion) | Nil |
| Ionic Radius (2+ ion) | 124 pm |
| Ionic Radius (2- ion) | Nil |
| Ionic Radius (3+ ion) | 115 pm |
|
| Conductivity |
| Thermal Conductivity | 6.3 J/m-sec-deg |
| Electrical Conductivity | Nil |
| Polarizability | 24.8 A3 |
|
| Abundance |
| Source | Synthetic |
| Relation Abundance Solar System | Nil |
| Abundance Earth's Crust | Nil |
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