Name Helium
Symbol He
Atomic Number 2
Atomic Mass 4.002602 atomic mass unit
Number of Protons 2
Number of Neutrons 2
Number of Electrons 2
Melting Point -272 C
Boiling Point -268.6 C
Density 0.1785 grams per cubic centimeter
Normal Phase Gas
Family Noble Gas
Period 1
Cost $37.50 per 1000 cubic feet



Origin of Name From the Greek word helios, meaning sun
Date and Place of Discovery 1868 in France and in England
1895 in England
Discovered by
Common Compounds
  • No stable compounds are formed with helium.
Interesting facts
  • It is created as a result of radioactive decay.
  • It is nonflammable.
  • Its the most abundant element known in the universe after hydrogen.
Common Uses
  • Main filling for blimps (airships)

  • Used to fill balloons

  • Detects leaks in sealed containers

  • Gas shield for arc welding

  • Growing silicon and germanium crystals for protective shields

  • Production of protective shields using titanium and zirconium

  • As a cooling factor in nuclear reactors

  • Artificial atmosphere created with 20% oxygen

  • Cryogenic applications (low temperature)

  • Pressurizing liquid fuel rockets


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Chemical Elements

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