Compare Thorium vs Selenium: Periodic Table Element Comparison Table and Properties
Compare the elements Thorium and Selenium on the basis of their properties, attributes and periodic table facts. Compare elements - Thorium and Selenium comparison table side by side across over 90 properties. All the elements of similar categories show a lot of similarities and differences in their chemical, atomic, physical properties and uses. These similarities and dissimilarities should be known while we study periodic table elements. You can study the detailed comparison between Thorium vs Selenium with most reliable information about their properties, attributes, facts, uses etc. You can compare Th vs Se on more than 90 properties like electronegativity, oxidation state, atomic shells, orbital structure, Electronaffinity, physical states, electrical conductivity and many more. This in-depth comparison helps students, educators, researchers, and science enthusiasts understand the differences and similarities between Thorium and Selenium.
Thorium and Selenium Comparison
Here's a detailed comparison between Thorium (Th) and Selenium (Se), focusing on their position in the periodic table, physical and chemical properties, stability, and uses.
Facts - Basic Element Details
| Name | Thorium | Selenium |
|---|---|---|
| Atomic Number | 90 | 34 |
| Atomic Symbol | Th | Se |
| Atomic Weight | 232.0381 | 78.96 |
| Phase at STP | Solid | Solid |
| Color | Silver | Gray |
| Metallic Classification | Actinide | Other Nonmetal |
| Group in Periodic Table | Actinide (no group number) | group 16 |
| Group Name | oxygen family | |
| Period in Periodic Table | period 7 | period 4 |
| Block in Periodic Table | f -block | p -block |
| Electronic Configuration | [Rn] 6d2 7s2 | [Ar] 3d10 4s2 4p4 |
| Electronic Shell Structure (Electrons per shell) | 2, 8, 18, 32, 18, 10, 2 | 2, 8, 18, 6 |
| Melting Point | 2023 K | 494 K |
| Boiling Point | 5093 K | 958 K |
| CAS Number | CAS7440-29-1 | CAS7782-49-2 |
| Neighborhood Elements | Neighborhood Elements of Thorium | Neighborhood Elements of Selenium |
History
| Parameter | Thorium | Selenium |
|---|---|---|
| History | The element Thorium was discovered by J. Berzelius in year 1829 in Sweden. Thorium derived its name from Thor, the Scandinavian god of thunder. | The element Selenium was discovered by J. Berzelius and G. Gahn in year 1817 in Sweden. Selenium derived its name from the Greek selene, meaning 'moon'. |
| Discovery | J. Berzelius (1829) | J. Berzelius and G. Gahn (1817) |
| Isolated | D. Lely, Jr. and L. Hamburger (1914) | J. Berzelius and G. Gahn (1817) |
Presence: Abundance in Nature and Around Us
Parts per billion (ppb) by weight / by atoms (1ppb =10^-7 %)
| Property | Thorium | Selenium |
|---|---|---|
| Abundance in Universe | 0.4 / 0.002 | 30 / 0.5 |
| Abundance in Sun | 0.3 / 0.002 | - / - |
| Abundance in Meteorites | 40 / 3 | 13000 / 2900 |
| Abundance in Earth's Crust | 6000 / 540 | 50 / 10 |
| Abundance in Oceans | 0.00004 / 0.0000011 | 0.45 / 0.035 |
| Abundance in Humans | - / - | 50 / 4 |
Crystal Structure and Atomic Structure
| Property | Thorium | Selenium |
|---|---|---|
| Atomic Volume | 19.7917 cm3/mol | 16.385 cm3/mol |
| Atomic Radius | 180 pm | 103 pm |
| Covalent Radius | - | 116 pm |
| Van der Waals Radius | - | 190 pm |
Atomic Spectrum - Spectral Lines | ||
| Emission Spectrum |  |  |
| Absorption Spectrum |  |  |
| Lattice Constant | 508.42, 508.42, 508.42 pm | 905.4, 908.3, 1160.1 pm |
| Lattice Angle | π/2, π/2, π/2 | π/2, 1.58493, π/2 |
| Space Group Name | Fm_ 3m | P121/c1 |
| Space Group Number | 225 | 14 |
| Crystal Structure | Face Centered Cubic  | Simple Monoclinic  |
Atomic and Orbital Properties
| Property | Thorium | Selenium |
|---|---|---|
| Atomic Number | 90 | 34 |
| Number of Electrons (with no charge) | 90 | 34 |
| Number of Protons | 90 | 34 |
| Mass Number | 232.0381 | 78.96 |
| Number of Neutrons | 142 | 45 |
| Shell structure (Electrons per energy level) | 2, 8, 18, 32, 18, 10, 2 | 2, 8, 18, 6 |
| Electron Configuration | [Rn] 6d2 7s2 | [Ar] 3d10 4s2 4p4 |
| Valence Electrons | 6d2 7s2 | 4s2 4p4 |
| Oxidation State | 4 | -2, 2, 4, 6 |
| Atomic Term Symbol (Quantum Numbers) | 3F2 | 3P2 |
| Shell structure |  |  |
Isotopes and Nuclear Properties
Thorium has 1 stable naturally occuring isotopes while Selenium has 5 stable naturally occuring isotopes.
| Parameter | Thorium | Selenium |
|---|---|---|
| Known Isotopes | 209Th, 210Th, 211Th, 212Th, 213Th, 214Th, 215Th, 216Th, 217Th, 218Th, 219Th, 220Th, 221Th, 222Th, 223Th, 224Th, 225Th, 226Th, 227Th, 228Th, 229Th, 230Th, 231Th, 232Th, 233Th, 234Th, 235Th, 236Th, 237Th, 238Th | 65Se, 66Se, 67Se, 68Se, 69Se, 70Se, 71Se, 72Se, 73Se, 74Se, 75Se, 76Se, 77Se, 78Se, 79Se, 80Se, 81Se, 82Se, 83Se, 84Se, 85Se, 86Se, 87Se, 88Se, 89Se, 90Se, 91Se, 92Se, 93Se, 94Se |
| Stable Isotopes | Naturally occurring stable isotopes: 232Th | Naturally occurring stable isotopes: 74Se, 76Se, 77Se, 78Se, 80Se |
| Neutron Cross Section | 7.4 | 11.7 |
| Neutron Mass Absorption | 0.001 | 0.0056 |
Chemical Properties: Ionization Energies and electron affinity
| Property | Thorium | Selenium |
|---|---|---|
| Valence or Valency | 4 | 6 |
| Electronegativity | 1.3 Pauling Scale | 2.55 Pauling Scale |
| Oxidation State | 4 | -2, 2, 4, 6 |
| Electron Affinity | - | 195 kJ/mol |
| Ionization Energies | 1st: 587 kJ/mol 2nd: 1110 kJ/mol 3rd: 1930 kJ/mol 4th: 2780 kJ/mol | 1st: 941 kJ/mol 2nd: 2045 kJ/mol 3rd: 2973.7 kJ/mol 4th: 4144 kJ/mol 5th: 6590 kJ/mol 6th: 7880 kJ/mol 7th: 14990 kJ/mol |
Physical Properties
Selenium (4.819 g/cm³) is less dense than Thorium (11.724 g/cm³). This means that a given volume of Thorium will be heavier than the same volume of Selenium. Thorium is about 143.3 denser than Selenium
| Property | Thorium | Selenium |
|---|---|---|
| Phase at STP | Solid | Solid |
| Color | Silver | Gray |
| Density | 11.724 g/cm3 | 4.819 g/cm3 |
| Density (when liquid (at melting point)) | - | 3.99 g/cm3 |
| Molar Volume | 19.7917 cm3/mol | 16.385 cm3/mol |
Mechanical and Hardness Properties
| Property | Thorium | Selenium |
|---|---|---|
Elastic Properties | ||
| Young Modulus | 79 | 10 |
| Shear Modulus | 31 GPa | 3.7 GPa |
| Bulk Modulus | 54 GPa | 8.3 GPa |
| Poisson Ratio | 0.27 | 0.33 |
Hardness - Tests to Measure of Hardness of Element | ||
| Mohs Hardness | 3 MPa | 2 MPa |
| Vickers Hardness | 350 MPa | - |
| Brinell Hardness | 400 MPa | 736 MPa |
Thermal and Electrical Conductivity
| Property | Thorium | Selenium |
|---|---|---|
Heat and Conduction Properties | ||
| Thermal Conductivity | 54 W/(m K) | 0.52 W/(m K) |
| Thermal Expansion | 0.000011 /K | - |
Electrical Properties | ||
| Electrical Conductivity | 6700000 S/m | - |
| Resistivity | 1.5e-7 m Ω | - |
| Superconducting Point | 1.38 | - |
Magnetic and Optical Properties
| Property | Thorium | Selenium |
|---|---|---|
Magnetic Properties | ||
| Magnetic Type | Paramagnetic | Diamagnetic |
| Curie Point | - | - |
| Mass Magnetic Susceptibility | 7.2e-9 m3/kg | -4e-9 m3/kg |
| Molar Magnetic Susceptibility | 1.7e-9 m3/mol | -3.16e-10 m3/mol |
| Volume Magnetic Susceptibility | 0.000084 | -0.0000193 |
Optical Properties | ||
| Refractive Index | - | 1.000895 |
Acoustic Properties | ||
| Speed of Sound | 2490 m/s | 3350 m/s |
Thermal Properties - Enthalpies and thermodynamics
| Property | Thorium | Selenium |
|---|---|---|
| Melting Point | 2023 K | 494 K |
| Boiling Point | 5093 K | 958 K |
| Critical Temperature | - | 1766 K |
| Superconducting Point | 1.38 | - |
Enthalpies | ||
| Heat of Fusion | 16 kJ/mol | 5.4 kJ/mol |
| Heat of Vaporization | 530 kJ/mol | 26 kJ/mol |
| Heat of Combustion | - | - |
Regulatory and Health - Health and Safety Parameters and Guidelines
| Parameter | Thorium | Selenium |
|---|---|---|
| CAS Number | CAS7440-29-1 | CAS7782-49-2 |
| RTECS Number | RTECSXO6400000 | {N/A, RTECSVS7700000, N/A} |
| DOT Hazard Class | 7 | 6.1 |
| DOT Numbers | 2975 | 2658 |
| EU Number | EU231-139-7 | - |
| NFPA Fire Rating | - | 0 |
| NFPA Health Rating | - | 2 |
| NFPA Reactivity Rating | - | 0 |
| NFPA Hazards | - | - |
| AutoIgnition Point | 130 °C | - |
| Flashpoint | - | - |
Compare Thorium and Selenium With Other Elements
Compare Thorium and Selenium with other elements of the periodic table. Explore howThorium and Selenium stack up against other elements of the periodic table. Use our interactive comparison tool to analyze 90+ properties across different metals, non-metals, metalloids, and noble gases. Understanding these differences is crucial for applications in engineering, chemistry, electronics, biology, and material science.