By: Jenn Stewart

Physical Propertiies

  • Atomic Mass: 4.002602 amu
  • Atomic Radius (in angstroms): 1.400
  • Density: 293k
  • Melting Point: -457.6 Fahrenheit (272.2 Celsius)
  • Boiling Point: -451.48 Fahrenheit (-268.6 Celsius)
  • It is a gas at room temperature
  • Appearance: colorless, odorless, red-orange glow when placed in a high voltage electric field
  • Conductivity: N/A
  • Malleability: N/A
  • Hardness: N/A

Chemical Properities

  • Flammability: non-flammable
  • Reactivity: it's least reactive

Atomic Structure

  • Atomic number: 2
  • Protons: 2
  • Electrons: 2
  • Neutrons: 2

It is located on the first row


  • When? Helium was discovered in 1868 by Pierre J. C. Janseen
  • Where? India
  • Who? Discovered by Pierre J. C. Janseen
  • How? Janseen observed a new yellow line in which indicated that there was a new element


  • Mainly used in balloons
  • Used in cooling medium for the Large Hadron Collider (LHC)
  • It's the superconducting magnets in MRI scanners and NMR scanners
  • There is a Helium-neon gas laser that are used to scan barcodes in checkouts

Fun Facts

  • The symbol is He
  • Helium has no known biological role because it is non-toxic
  • A mixture of 80% helium and 20% oxygen is used for deep sea divers and others working under pressurized conditions
  • It's a Nobel gas
  • Named after the Greek god of the sun, Helios