Helium is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first element in the noble gas group in the periodic table.
Has the lowest boiling point from all the elements.
Is the second lightest and second most abundant element in the universe.
Most helium in the universe is helium 4, the vast majority of which was formed during the Big Bang.
Helium is created by nuclear fusion of hydrogen in stars.
On Earth, helium is rare, most of it is created by natural radioactive decay of heavy elements as alpha particles.
Helium is used as plasma phase in light tubes with a orange glow.
At low temperature, helium will remain liquid down to absolute zero at normal pressure, a strange and unique ability among all the elements, the zero point energy of the system is too high to allow freezing.
Solid helium can be made at a temperature of about -272 °C / 1-1,5 K and about 25 bar pressure.
The most known use of helium is balloons, as they are lighter then oxygen and not dangerous.
Helium is used for it's low boiling point, low density, low solubility and inertness.
Gas tugstein arc welding is an important use of helium.
MMR use helium as coolant for the superconducting magnets.
Being lighter then oxygen, human voice will have higher pitch when breathing helium and talking.
Properties:
Atomic number 2; Atomic weight 4,002602
Phase gas
Melting point -272 °C
Boiling point -268,93 °C
Density 0,1786 g/L
Crystal structure: hexagonal close packed
Speed of sound in gas 972 m/s
Magnetism: diamagnetic
Abundance: 23% in universe; 23% in sun
Isotopes:
Helium 3 - abundance 0,000137% - stable
Helium 4 - abundange 99,999863% - stable
H2; H5, H6, H7, H8, H9, H10
Helium 3 also named tralphium is a lighter then normal helium (helium 4), non-radioactive isotope with 2 protons and one neutron.
Unlike most other nuclear fusion reactions, the fusion of helium 3 atoms releases large amounts of energy without causing the surrounding material to become radioactive but to achieve helium 3 fusion, the temperatures required are much higher than traditional fusion reactions.
It can be used to make lighter materials and balloons.
It is believed taht the Moon has a greater abundance of helium 3 than the Earth.
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