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49In

Element 49

Indium

Post-transition metals

Indium (In) is in the p-block of the periodic table — group 13, period 5.

Indium is a chemical element with symbol In and atomic number 49.

Key data

Atomic number
49
Atomic mass
114.818 u
Group / Period
13 / 5
Block
p-block
Phase at STP
Solid
Density
7.31 g/cm³
Melting point
156.6 °C
Boiling point
2071.8 °C
Electron configuration
[Kr] 4d10 5s2 5p1

Periodic table block

Indium is in the p-block (group 13, period 5). Elements land in the p-block when their highest-energy electrons fill a p subshell — this region holds most nonmetals, the metalloids, and the metals on the right of the table.

s-blockp-blockd-blockf-block

New to this? Periodic table blocks explained: s, p, d, and f

Common uses

  • Touchscreens (ITO)
  • LCDs
  • Solder

Discovery

Year: 1863

Discovered by: Ferdinand Reich

Frequently asked questions

What is the atomic number of Indium?

Indium has atomic number 49. Its symbol is In and its atomic mass is 114.818 u.

What category of element is Indium?

Indium is classified as post-transition metals. It sits in group 13, period 5 of the periodic table.

What block of the periodic table is Indium in?

Indium is in the p-block (group 13, period 5). Its highest-energy electrons occupy the p subshell — you can see this in its electron configuration, [Kr] 4d10 5s2 5p1.

What is Indium used for?

Common uses of Indium include: Touchscreens (ITO), LCDs, Solder.

When was Indium discovered?

Indium was discovered in 1863 by Ferdinand Reich.

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