Selenium,  34Se
ସାଧାରଣ ଗୁଣ
ନାମ, ପ୍ରତୀକselenium, Se
Appearanceblack and red allotropes
ଉଚ୍ଚାରଣ/s[invalid input: 'ɨ']ˈlniəm/ si-LEE-nee-əm
Selenium in the periodic table
Hydrogen (other non-metal)
Helium (noble gas)
Lithium (alkali metal)
Beryllium (alkaline earth metal)
Boron (metalloid)
Carbon (other non-metal)
Nitrogen (other non-metal)
Oxygen (other non-metal)
Fluorine (halogen)
Neon (noble gas)
Sodium (alkali metal)
Magnesium (alkaline earth metal)
Aluminium (post-transition metal)
Silicon (metalloid)
Phosphorus (other non-metal)
Sulfur (other non-metal)
Chlorine (halogen)
Argon (noble gas)
Potassium (alkali metal)
Calcium (alkaline earth metal)
Scandium (transition metal)
Titanium (transition metal)
Vanadium (transition metal)
Chromium (transition metal)
Manganese (transition metal)
Iron (transition metal)
Cobalt (transition metal)
Nickel (transition metal)
Copper (transition metal)
Zinc (transition metal)
Gallium (post-transition metal)
Germanium (metalloid)
Arsenic (metalloid)
Selenium (other non-metal)
Bromine (halogen)
Krypton (noble gas)
Rubidium (alkali metal)
Strontium (alkaline earth metal)
Yttrium (transition metal)
Zirconium (transition metal)
Niobium (transition metal)
Molybdenum (transition metal)
Technetium (transition metal)
Ruthenium (transition metal)
Rhodium (transition metal)
Palladium (transition metal)
Silver (transition metal)
Cadmium (transition metal)
Indium (post-transition metal)
Tin (post-transition metal)
Antimony (metalloid)
Tellurium (metalloid)
Iodine (halogen)
Xenon (noble gas)
Caesium (alkali metal)
Barium (alkaline earth metal)
Lanthanum (lanthanoid)
Cerium (lanthanoid)
Praseodymium (lanthanoid)
Neodymium (lanthanoid)
Promethium (lanthanoid)
Samarium (lanthanoid)
Europium (lanthanoid)
Gadolinium (lanthanoid)
Terbium (lanthanoid)
Dysprosium (lanthanoid)
Holmium (lanthanoid)
Erbium (lanthanoid)
Thulium (lanthanoid)
Ytterbium (lanthanoid)
Lutetium (lanthanoid)
Hafnium (transition metal)
Tantalum (transition metal)
Tungsten (transition metal)
Rhenium (transition metal)
Osmium (transition metal)
Iridium (transition metal)
Platinum (transition metal)
Gold (transition metal)
Mercury (transition metal)
Thallium (post-transition metal)
Lead (post-transition metal)
Bismuth (post-transition metal)
Polonium (post-transition metal)
Astatine (halogen)
Radon (noble gas)
Francium (alkali metal)
Radium (alkaline earth metal)
Actinium (actinoid)
Thorium (actinoid)
Protactinium (actinoid)
Uranium (actinoid)
Neptunium (actinoid)
Plutonium (actinoid)
Americium (actinoid)
Curium (actinoid)
Berkelium (actinoid)
Californium (actinoid)
Einsteinium (actinoid)
Fermium (actinoid)
Mendelevium (actinoid)
Nobelium (actinoid)
Lawrencium (actinoid)
Rutherfordium (transition metal)
Dubnium (transition metal)
Seaborgium (transition metal)
Bohrium (transition metal)
Hassium (transition metal)
Meitnerium (unknown chemical properties)
Darmstadtium (unknown chemical properties)
Roentgenium (unknown chemical properties)
Copernicium (transition metal)
Ununtrium (unknown chemical properties)
Flerovium (unknown chemical properties)
Ununpentium (unknown chemical properties)
Livermorium (unknown chemical properties)
Ununseptium (unknown chemical properties)
Ununoctium (unknown chemical properties)
S

Se

Te
arsenicseleniumbromine
ପରମାଣୁ କ୍ରମାଙ୍କ (Z)34
ଶ୍ରେଣୀ, ବ୍ଳକgroup 16 (chalcogens), p-block
ପର୍ଯ୍ୟାୟperiod 4
ମୌଳିକ ପ୍ରକାର  nonmetal, sometimes considered a metalloid
ମାନକ ପରମାଣବିକ ଓଜନ (Ar)78.96
ଇଲେକ୍‌ଟ୍ରୋନ୍ ବିନ୍ୟାସ[Ar] 3d10 4s2 4p4
per shell
2, 8, 18, 6
ଭୌତିକ ଗୁଣ
ଅବସ୍ଥାsolid
ଗଳନାଙ୍କ494 K ​(221 °C, ​430 °F)
ସ୍ଫୁଟନାଙ୍କ958 K ​(685 °C, ​1265 °F)
Density near r.t.(gray) 4.81 g/cm3
(alpha) 4.39 g/cm3
(vitreous) 4.28 g/cm3
when liquid, at m.p.3.99 g/cm3
Critical point1766 K, 27.2 MPa
Heat of fusion(gray) 6.69 kJ/mol
Heat of 95.48 kJ/mol
Molar heat capacity25.363 J/(mol·K)
 pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 500 552 617 704 813 958
Atomic properties
Oxidation states6, 4, 2, 1,[] -2
(strongly acidic oxide)
ElectronegativityPauling scale: 2.55
Atomic radiusempirical: 120 pm
Covalent radius120±4 pm
Van der Waals radius190 pm
Miscellanea
Crystal structurehexagonal
Hexagonal crystal structure for selenium
Speed of sound thin rod3350 m/s (at 20 °C)
Thermal expansion(amorphous) 37 µm/(m·K) (at 25 °C)
Thermal conductivity(amorphous) 0.519 W/(m·K)
Magnetic orderingdiamagnetic[]
Young's modulus10 GPa
Shear modulus3.7 GPa
Bulk modulus8.3 GPa
Poisson ratio0.33
Mohs hardness2.0
Brinell hardness736 MPa
CAS Number7782-49-2
ଇତିହାସ
ଆବିଷ୍କାରJöns Jakob Berzelius and Johann Gottlieb Gahn (1817)
First isolationJöns Jakob Berzelius and Johann Gottlieb Gahn (1817)
Most stable isotopes of selenium
iso NA half-life DM DE (MeV) DP
72Se syn 8.4 d ε - 72As
γ 0.046 -
74Se 0.87% 74Se is stable with 40 neutrons
75Se syn 119.779 d ε - 75As
γ 0.264, 0.136,
0.279
-
76Se 9.36% 76Se is stable with 42 neutrons
77Se 7.63% 77Se is stable with 43 neutrons
78Se 23.78% 78Se is stable with 44 neutrons
79Se trace 3.27×105 y β 0.151 79Br
80Se 49.61% 80Se is stable with 46 neutrons
82Se 8.73% 1.08×1020 y ββ 2.995 82Kr
| references

References

  1. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 0080379419.
  2. Magnetic susceptibility of the elements and inorganic compounds, in Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5.