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Thallium (Tl)
Atomic number: 81 · Category: post-transition metal · Group 13 · Period 6 · Phase: Solid
Thallium is a chemical element with symbol Tl and atomic number 81. This soft gray post-transition metal is not found free in nature. When isolated, it resembles tin, but discolors when exposed to air.
Atomic mass: 204.38
Density: 11.85
Melting point: 577 K
Boiling point: 1746 K
Appearance: silvery white
Source: Wikipedia
Block: p
Molar heat: 26.32
CPK color:#a6544d
Electronic structure
Electron configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p1
Configuration (semantic): [Xe] 4f14 5d10 6s2 6p1
Shells: 2, 8, 18, 32, 18, 3
Electronegativity (Pauling): 1.62
Electron affinity: 36.4
Ionization energies: 589.4, 1971, 2878
Periodic position
Group: 13
Period: 6
xpos: 13
ypos: 6
Spectral/Bohr images
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3D Model