Periodic Table Element Comparison: Compare Elements - Selenium vs Cobalt
Compare Selenium and Cobalt on the basis of their properties, attributes and periodic table facts. Compare elements on more than 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 Selenium vs Cobalt with most reliable information about their properties, attributes, facts, uses etc. You can compare Se vs Co on more than 90 properties like electronegativity , oxidation state, atomic shells, orbital structure, Electronaffinity, physical states, electrical conductivity and many more. Selenium and Cobalt comparison table on more than 90 properties.
Selenium and Cobalt Comparison
Facts
| Name | Selenium | Cobalt |
|---|---|---|
| Atomic Number | 34 | 27 |
| Atomic Symbol | Se | Co |
| Atomic Weight | 78.96 | 58.9332 |
| Phase at STP | Solid | Solid |
| Color | Gray | Gray |
| Metallic Classification | Other Nonmetal | Transition Metal |
| Group in Periodic Table | group 16 | group 9 |
| Group Name | oxygen family | cobalt family |
| Period in Periodic Table | period 4 | period 4 |
| Block in Periodic Table | p -block | d -block |
| Electronic Configuration | [Ar] 3d10 4s2 4p4 | [Ar] 3d7 4s2 |
| Electronic Shell Structure (Electrons per shell) | 2, 8, 18, 6 | 2, 8, 15, 2 |
| Melting Point | 494 K | 1768 K |
| Boiling Point | 958 K | 3200 K |
| CAS Number | CAS7782-49-2 | CAS7440-48-4 |
| Neighborhood Elements | Neighborhood Elements of Selenium | Neighborhood Elements of Cobalt |
History
| Parameter | Selenium | Cobalt |
|---|---|---|
| History | 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'. | The element Cobalt was discovered by G. Brandt in year 1735 in Sweden. Cobalt derived its name from the German word Kobold, meaning 'goblin'. |
| Discovery | J. Berzelius and G. Gahn (1817) | G. Brandt (1735) |
| Isolated | J. Berzelius and G. Gahn (1817) | G. Brandt (1735) |
Presence: Abundance in Nature and Around Us
Parts per billion (ppb) by weight / by atoms (1ppb =10^-7 %)
| Property | Selenium | Cobalt |
|---|---|---|
| Abundance in Universe | 30 / 0.5 | 3000 / 60 |
| Abundance in Sun | - / - | 4000 / 70 |
| Abundance in Meteorites | 13000 / 2900 | 600000 / 200000 |
| Abundance in Earth's Crust | 50 / 10 | 30000 / 10000 |
| Abundance in Oceans | 0.45 / 0.035 | 0.08 / 0.008 |
| Abundance in Humans | 50 / 4 | 20 / 2 |
Crystal Structure and Atomic Structure
| Property | Selenium | Cobalt |
|---|---|---|
| Atomic Volume | 16.385 cm3/mol | 6.62 cm3/mol |
| Atomic Radius | 103 pm | 152 pm |
| Covalent Radius | 116 pm | 126 pm |
| Van der Waals Radius | 190 pm | - |
Atomic Spectrum - Spectral Lines | ||
| Emission Spectrum |  |  |
| Absorption Spectrum |  |  |
| Lattice Constant | 905.4, 908.3, 1160.1 pm | 250.71, 250.71, 406.95 pm |
| Lattice Angle | π/2, 1.58493, π/2 | π/2, π/2, 2 π/3 |
| Space Group Name | P121/c1 | P63/mmc |
| Space Group Number | 14 | 194 |
| Crystal Structure | Simple Monoclinic  | Simple Hexagonal  |
Atomic and Orbital Properties
| Property | Selenium | Cobalt |
|---|---|---|
| Atomic Number | 34 | 27 |
| Number of Electrons (with no charge) | 34 | 27 |
| Number of Protons | 34 | 27 |
| Mass Number | 78.96 | 58.9332 |
| Number of Neutrons | 45 | 32 |
| Shell structure (Electrons per energy level) | 2, 8, 18, 6 | 2, 8, 15, 2 |
| Electron Configuration | [Ar] 3d10 4s2 4p4 | [Ar] 3d7 4s2 |
| Valence Electrons | 4s2 4p4 | 3d7 4s2 |
| Oxidation State | -2, 2, 4, 6 | 2, 3 |
| Atomic Term Symbol (Quantum Numbers) | 3P2 | 4F9/2 |
| Shell structure |  |  |
Isotopes and Nuclear Properties
Selenium has 5 stable naturally occuring isotopes while Cobalt has 1 stable naturally occuring isotopes.
| Parameter | Selenium | Cobalt |
|---|---|---|
| Known Isotopes | 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 | 47Co, 48Co, 49Co, 50Co, 51Co, 52Co, 53Co, 54Co, 55Co, 56Co, 57Co, 58Co, 59Co, 60Co, 61Co, 62Co, 63Co, 64Co, 65Co, 66Co, 67Co, 68Co, 69Co, 70Co, 71Co, 72Co, 73Co, 74Co, 75Co |
| Stable Isotopes | Naturally occurring stable isotopes: 74Se, 76Se, 77Se, 78Se, 80Se | Naturally occurring stable isotopes: 59Co |
| Neutron Cross Section | 11.7 | 37.2 |
| Neutron Mass Absorption | 0.0056 | 0.021 |
Chemical Properties: Ionization Energies and electron affinity
| Property | Selenium | Cobalt |
|---|---|---|
| Valence or Valency | 6 | 4 |
| Electronegativity | 2.55 Pauling Scale | 1.88 Pauling Scale |
| Electron Affinity | 195 kJ/mol | 63.7 kJ/mol |
| Ionization Energies | 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 | 1st: 760.4 kJ/mol 2nd: 1648 kJ/mol 3rd: 3232 kJ/mol 4th: 4950 kJ/mol 5th: 7670 kJ/mol 6th: 9840 kJ/mol 7th: 12440 kJ/mol 8th: 15230 kJ/mol 9th: 17959 kJ/mol 10th: 26570 kJ/mol 11th: 29400 kJ/mol 12th: 32400 kJ/mol 13th: 36600 kJ/mol 14th: 39700 kJ/mol 15th: 42800 kJ/mol 16th: 49396 kJ/mol 17th: 52737 kJ/mol 18th: 134810 kJ/mol 19th: 145170 kJ/mol 20th: 154700 kJ/mol 21st: 167400 kJ/mol 22nd: 178100 kJ/mol 23rd: 189300 kJ/mol 24th: 204500 kJ/mol 25th: 214100 kJ/mol 26th: 920870 kJ/mol 27th: 966023 kJ/mol |
Physical Properties
| Property | Selenium | Cobalt |
|---|---|---|
| Density | 4.819 g/cm3 | 8.9 g/cm3 |
| Molar Volume | 16.385 cm3/mol | 6.62 cm3/mol |
Elastic Properties | ||
| Young Modulus | 10 | 209 |
| Shear Modulus | 3.7 GPa | 75 GPa |
| Bulk Modulus | 8.3 GPa | 180 GPa |
| Poisson Ratio | 0.33 | 0.31 |
Hardness - Tests to Measure of Hardness of Element | ||
| Mohs Hardness | 2 MPa | 5 MPa |
| Vickers Hardness | - | 1043 MPa |
| Brinell Hardness | 736 MPa | 700 MPa |
Electrical Properties | ||
| Electrical Conductivity | - | 17000000 S/m |
| Resistivity | - | 6e-8 m Ω |
| Superconducting Point | - | - |
Heat and Conduction Properties | ||
| Thermal Conductivity | 0.52 W/(m K) | 100 W/(m K) |
| Thermal Expansion | - | 0.000013 /K |
Magnetic Properties | ||
| Magnetic Type | Diamagnetic | Ferromagnetic |
| Curie Point | - | 1394 K |
| Mass Magnetic Susceptibility | -4e-9 m3/kg | - |
| Molar Magnetic Susceptibility | -3.16e-10 m3/mol | - |
| Volume Magnetic Susceptibility | -0.0000193 | - |
Optical Properties | ||
| Refractive Index | 1.000895 | - |
Acoustic Properties | ||
| Speed of Sound | 3350 m/s | 4720 m/s |
Thermal Properties - Enthalpies and thermodynamics
| Property | Selenium | Cobalt |
|---|---|---|
| Melting Point | 494 K | 1768 K |
| Boiling Point | 958 K | 3200 K |
| Critical Temperature | 1766 K | - |
| Superconducting Point | - | - |
Enthalpies | ||
| Heat of Fusion | 5.4 kJ/mol | 16.2 kJ/mol |
| Heat of Vaporization | 26 kJ/mol | 375 kJ/mol |
| Heat of Combustion | - | - |
Regulatory and Health - Health and Safety Parameters and Guidelines
| Parameter | Selenium | Cobalt |
|---|---|---|
| CAS Number | CAS7782-49-2 | CAS7440-48-4 |
| RTECS Number | {N/A, RTECSVS7700000, N/A} | RTECSGF8750000 |
| DOT Hazard Class | 6.1 | 4.1 |
| DOT Numbers | 2658 | 3089 |
| EU Number | - | - |
| NFPA Fire Rating | 0 | - |
| NFPA Health Rating | 2 | - |
| NFPA Reactivity Rating | 0 | - |
| NFPA Hazards | - | - |
| AutoIgnition Point | - | - |
| Flashpoint | - | - |
Compare With Other Elements
Compare Selenium and Cobalt with other elements of the periodic table.