43 - Technetium transition metal

Discovered by Emilio Segrè in 1937

  • Atomic Radius (Å)
  • Cividis
Technetium

Technetium (/tɛkˈniːʃiəm/) is a chemical element with symbol Tc and atomic number 43. It is the element with the lowest atomic number in the periodic table that has no stable isotopes:every form of it is radioactive. Nearly all technetium is produced synthetically, and only minute amounts are found in nature.

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
122 in 1s
282 in 2s + 6 in 2p
3182 in 3s + 6 in 3p + 10 in 3d
4132 in 4s + 6 in 4p + 5 in 4d
522 in 5s
TechnetiumTcElectron 1Electron 2Electron 1Electron 2Electron 3Electron 4Electron 5Electron 6Electron 7Electron 8Electron 1Electron 2Electron 3Electron 4Electron 5Electron 6Electron 7Electron 8Electron 9Electron 10Electron 11Electron 12Electron 13Electron 14Electron 15Electron 16Electron 17Electron 18Electron 1Electron 2Electron 3Electron 4Electron 5Electron 6Electron 7Electron 8Electron 9Electron 10Electron 11Electron 12Electron 13Electron 1Electron 2
shiny gray metal Appearance
98  u Atomic Mass
1.35  Å Atomic Radius
5.15k  K Boiling Point
7 Group
4, 7 Common Oxidation States
1.47  Å Covalent Radius
11  g/cm³ Density
53  kJ/mol Electron Affinity
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d5 Electron Configuration
[Kr] 4d5 5s2 Electron Configuration (semantic)
1.9 Electronegativity
43 Electrons
7.28  eV First Ionization Energy
702, 1470, 2850  kJ/mol Ionization Energies
2.47k  K Melting Point
59 Mendeleev Number
24.3  J/(mol·K) Molar Heat
5 Number of Shells
55 Neutrons
43 Atomic Number
23 Number of Isotopes
-3, -1, 1, 2, 3, 4, 5, 6, 7 Oxidation States
5 Period
Solid Phase
43 Protons