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85 - Astatine metalloid

Discovered by Dale R. Corson in 1940

Astatine

Astatine is a very rare radioactive chemical element with the chemical symbol At and atomic number 85. It occurs on Earth as the decay product of various heavier elements. All its isotopes are short-lived; the most stable is astatine-210, with a half-life of 8.1 hours.

H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
57-71 La-Lu Lanthanides
89-103 Ac-Lr Actinides
Shell Electrons Orbitals
1 2 2 in 1s
2 8 2 in 2s + 6 in 2p
3 18 2 in 3s + 6 in 3p + 10 in 3d
4 32 2 in 4s + 6 in 4p + 10 in 4d + 14 in 4f
5 18 2 in 5s + 6 in 5p + 10 in 5d
6 7 2 in 6s + 5 in 6p
AstatineAt Electron 1 Electron 2 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 10 Electron 11 Electron 12 Electron 13 Electron 14 Electron 15 Electron 16 Electron 17 Electron 18 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 10 Electron 11 Electron 12 Electron 13 Electron 14 Electron 15 Electron 16 Electron 17 Electron 18 Electron 19 Electron 20 Electron 21 Electron 22 Electron 23 Electron 24 Electron 25 Electron 26 Electron 27 Electron 28 Electron 29 Electron 30 Electron 31 Electron 32 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 10 Electron 11 Electron 12 Electron 13 Electron 14 Electron 15 Electron 16 Electron 17 Electron 18 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7
210  u Atomic Mass
1.4  Å Atomic Radius
610  K Boiling Point
1.5  Å Covalent Radius
6.35  g/cm³ Density
233 Electron Affinity
2.2 Electronegativity
9.3  eV First Ionization Energy
575  K Melting Point
6 Number of Shells
7 Electron Valency
85 Atomic Number