Helium is the 2nd and 2nd lightest element in the periodic table. The symbol for it is He and it weighs 4.003 u. It is a noble gas, and it does not react with anything and is virtually inert. Helum is used in aircraft and hot air balloons, and in lighting. It is often used in reasearch too.
Atomic name: Helium Colour: Colourless
Atomic number: 2 Melting point: 0.95 K (-272.20 C, -457.96 F)
Atomic weight: 4.003 u Boiling point: 4.22 K (-268.928 C, -452.07 F )
Element Category: Noble gas