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thallium
Image: Wikimedia Commons

thallium

Chemical element with symbol Tl and atomic number 81

Chemical elementchemical elementchalcophile elementQ932

Also known as element 81 · 81Tl

Symbol
Atomic number
  • 81
Mass
Melting point
  • 577 K
Boiling point
  • 1,733 K
Density
  • 11,348.4 kg/m³
Discovered by
Discovered
  • 1861

Overview

All data

135 statements · 24% with external sources · numbers in brackets are citations

Has effect
Canonical SMILES
Formula
Unicode character
Electronegativity
  • 1.62
Part of
Named after
Ionic radius
  • 1.5 ångström charge number: 1 · coordination number: 6
  • 1.59 ångström charge number: 1 · coordination number: 8
  • 1.7 ångström charge number: 1 · coordination number: 12
  • 0.75 ångström charge number: 3 · coordination number: 4
  • 0.89 ångström charge number: 3 · coordination number: 6
  • 0.98 ångström charge number: 3 · coordination number: 8
Different from
Associated hazard
Space group
Crystal system
Bulk modulus
  • 26.4B Pa
Shear modulus
  • 11.2B Pa
Poisson's ratio
  • 0.315
Thermal conductivity
  • 46 watt per metre kelvin
Electrical conductivity
  • 6,670,000 siemens per metre
Specific heat capacity
  • 129 joule per kilogram kelvin
Speed of sound
  • 818 m/s
Electrical resistivity
  • 1.8e-7 ohm metre
Point group
Mohs' hardness
  • 1.2
Has characteristic
Linear thermal expansion coefficient
  • 29.9 micrometre per metre kelvin temperature: 25°C
Ionization energy
Subclass of
Electron configuration
IPA transcription
Oxidation state
  • 1
  • 3
  • -5
  • -2
  • -1
  • 2
Atomic radius
  • 190 picometre
Covalent radius
  • 145 picometre
Van der Waals radius
  • 196 picometre

On other databases

68 identifiers linking thallium across the web's reference databases