49
In
Post-transition metal

Indium

Atomic number 49 · Period 5 · Block P

In · Indium
Mendeleev.com

Understanding the element

Indium (In) is chemical element 49. It belongs to the post-transition metals, and its reference state at room temperature is a solid. Those basic facts are a useful starting point for its chemistry and applications.

Where do we encounter it?

In practice, it turns up most often in touch screens, semiconductors and alloys.

touch screenssemiconductorsalloys
Standard atomic weight114.818(1)

What its position in the table tells us

Indium sits in period 5, group 13 and the P block. That location is useful because neighbouring elements often share trends in valence electrons, oxidation states and bonding behaviour.

Worth remembering
Indium has a characteristic place in the periodic table that helps explain both its chemistry and its practical uses

Scientific sources

Element identity
Atomic number49
Group13
Period5
BlockP
CategoryPost-transition metal
PhaseSolid