Indium (In) VS Thallium (Tl)
A definitive side-by-side comparison of two essential element profiles.
VS
Main Differences
Indium (In) is an element in the post-transition metals category with an atomic number of 49. Thallium (Tl) is an element in the post-transition metals category with an atomic number of 81.
Thallium (Tl) is 1.6x denser than Indium (In). However, Thallium (Tl) melts at a higher temperature than Indium (In) (a difference of 147.3 Kelvin).
Where do the names come from?
In Indium (In) Naming History
The name Indium comes from the Latin ''indicium'', meaning violet or indigo.
Tl Thallium (Tl) Naming History
Thallium is derived from the Greek ''thallos'', meaning a green twig.
Related Comparisons
Compare
Indium (In)
Thallium (Tl)
Category
Post-transition Metals
Post-transition Metals
Atomic Number
49
81
Symbol
In
Tl
Atomic Mass
114.818 u
204.38 u
Group
13
13
Period
5
6
Block
p-block
p-block
Standard State (at 20°C)
solid
solid
Density
7.31 g/cm³
11.85 g/cm³
Melting Point (°C)
156.60°C
304°C
Melting Point (°F)
313.88°F
579°F
Melting Point (K)
429.75 K
577 K
Boiling Point (°C)
2027°C
1473°C
Boiling Point (°F)
3681°F
2683°F
Boiling Point (K)
2345 K
1746 K
Year Discovered:
1863
1861
CAS Number
7440-74-6
7440-28-0
Origin of Name:
The name comes from the Latin ''indicium'', meaning violet or indigo.
Thallium is derived from the Greek ''thallos'', meaning a green twig.