![]() Helium(He)-neon(Ne) gas lasers are used to scan barcodes in supermarket checkouts. Ratios of He and O 2 can be changes for different diver opration depths. ![]() Helium is used as pressurizing gas in Liquid propellant (fuel) for Rockets, and in a Helium(80%)-Oxygen(20%) mixture, which is used as an artificial atmosphere for deep-sea divers and others working. Helium is also used as Mass Spectrometer Leak Detector (MSLD) to detect leaks, such as in car air-conditioning systems, and because of it diffuses (spread) quickly, it is used in the Car Airbags to inflate (fill with air or gas) after impact. Hydrogen is also very light but cant used in these applications, because it is dangerously reactive, and helium is much safer than hydrogen. Helium is used as a gas for Supersonic wind tunnels.īecause of its low density, Helium is very light weighted gas and is often used to fill Decorative balloons, Weather balloons, and Airships (dirigibles ballons). It is also used to keep cool the Satellite instrument, Liquid oxygen, and Liquid Hydrogen. ![]() Thats why Helium is used in Cryogenic research, and also used as a cooling medium for the Large Hadron Collider (LHC), as well as a working fluid in Nuclear reactors cooled down by gas, and for the superconducting magnets in MRI (magnetic resonance imaging) scanners and NMR Spectrometers, and in the development of the superconductivity state, where the resistance to the electricity flux is almost zero. Helium is the only element which is capable to reaching temperatures lower than 15 K ( 258.15✬, -434✯). Silicon and Germanium crystals are used to make fiber optics and electronic semiconductor devices. It is also used as a protective gas (non-reactive atmosphere) for growing Silicon & Germanium crystals and producing Titanium & Zirconium. Helium is non reactive element, so it is used as an inert gas shield in robotic Arc welding. Naming: After Helios, (Greek Titan of the sun)ĭiscovery: Pierre Janssen, Norman Lockyer (1868)įirst isolation:Willian Ramsay, Per Teodor cleve, Abraham Langlet (1895), London (England) / Uppsala (Sweden) Helium Uses It doesnt react with Air, Water, Halogens, Acid, Bases etc… Fission and Fusion Equations:įission Reaction of Uranium 235 (U-235) Bombarded by Neutrons:ġ 0n + 235 92U → 141 56Ba + 92 36Kr + 3 1 0nģ 2He + 3 2He → 4 2He + 2 1 1P + 12.85 MeV orĭ ( 2 1H) + 3 2He → 4 2He + 1 1P + 18.4 MeV Helium History Hexagonal Close Packed (HCP) Reactivity of HeliumĮlectron affinity: 0 kJ/mol Nuclear Properties of Helium Ionization energies: 1st: 2372.2 kJ.mol 2nd: 5250.5 kJ/molĬrystal structure: Hexagonal close-packed The ionization potential of an atom: 24.47 eV Sound Speed: 972 m/s Atomic Properties of Helium Molar magnetic susceptibility: -236×10 -9 m 3/mol Physical Properties of Heliumĭensity: 0.178 g/L (at STP) 0.145 g/cm 3 (In Liquid at M.P) Mass magnetic susceptibility: -5.9×10 -9 m 3/kg ![]() Magnetic susceptibility (x mol): -1.88×10 -6 cm 3/mol Neel Point (magnetic ordering temperature) T N: N/A Electrical properties of HeliumĬritical point (Superconducting point): N/A Magnetic Properties of Helium Helium Electron Configuration Thermal Properties of Helium It is the only element that cannot be solidified by lowering the temperature, It remains liquid down to absolute zero at normal pressures, but it can readily solidify by increasing the pressure. It has many unique properties such as low density, low boiling point, low solubility, high thermal conductivity and inertness (less reactive). Helium is a Odourless, Colourless, insipid and non-toxic gas.
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