Helium
Atomic symbol: He
Atomic number: 2
Atomic mass: 4.00
Appearance: colorless gas at 25°C
Group: 0 / 18
Period: 1
Series: noble gases
Block: s
Electron configuration: 1s²
The second lightest and most abundant element after hydrogen.
Non-toxic and inert.
Fun Fact!
Helium ballons can escape into space! This is because helium is so light that not even Earth’s gravity can hold it.