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He

Helium

Atomic number: 2Mass: 4.0026 uCategory: Noble Gas

About Helium

Helium is a colourless, odourless, tasteless, non-toxic, inert monatomic gas. It is the first noble gas and the second lightest element. Helium has the lowest boiling point of all elements.

Properties

Period
1
Group
18
Block
P
Category
Noble Gas
Electronegativity
N/A
Ionization Energy
2372 kJ/mol
Melting Point
Unknown
Boiling Point
4 K (-269°C)
Density
0.178 g/L
Oxidation States
None

Electron Configuration

1s²
1s²
Shell 1:2e⁻

Real-World Uses

Weather balloons
MRI machines
Party balloons
Cryogenics
Airships

Fun Fact

Helium was discovered in the Sun before it was found on Earth — its name comes from Helios, the Greek god of the Sun.