Periodic table of the elements
MercuryThalliumLead
81
Tl
Thallium
204.3833
2
8
18
32
18
3
81
Tl
Thallium
204.3833
2
8
18
32
18
3
General
NameThallium
SymbolTl
Number81
Chemical seriesOther metals
Group / Period13 / 6
Blockp-block
CAS registry number7440-28-0

Physical properties
Statesolid
Density11.85 g/cm3
Melting point577 K (304 °C, 579 °F
Boiling point1746 K (1473 °C, 2683 °F)
Critical point

Atomic properties
Atomic Weight204.3833 g/mol
Crystal structurehexagonal
Electronegativity1.62
Atomic radius190 pm
Atomic radius (calculated)156 pm
Electron configuration[Xe] 4f14 5d10 6s2 6p1
Electrons per shell2, 8, 18, 32, 18, 3
Number of protons81
Number of neutrons123

Other languages
SpanishTalio
PortugueseTálio
FrenchThallium
GermanThallium
ItalianTallio
RussianТаллий
PolishTal
Chinese
Arabicثاليوم
TurkishTalyum
DutchThallium


Periodic table of the elements
MercuryThalliumLead