What Is Heliums Atomic Mass

Helium - He

Chemic properties of helium - Wellness effects of helium

Atomic number	two
Atomic mass	4.00260 g.mol^-1
Electronegativity according to Pauling	unknown
Density	0.178*10^-3 grand.cm^-3 at 20 °C
Melting indicate	- 272.2 (26 atm) °C
Boiling point	- 268.9 °C
Vanderwaals radius	0.118 nm
Ionic radius	unknown
Isotopes	2
Electronic shell	1s ⁱⁱ
Energy of kickoff ionisation	2372 kJ.mol^-1
Discovered by	^{Sir Ramsey in 1895}

Helium - He

Helium

Backdrop

Gaseous chemical element, symbol: He, atomic number: ii and atomic weight iv,0026 g/mol. Helium is one of the noble gases of group O in the periodic table. It's the second lightest chemical element. The main helium source in the world is a serial of fields of natural gas in the United States.

Helium is a colourless, odourless, insipid and not-toxic gas. Information technology'southward less soluble in water than whatever other gas. Information technology's the less reactive chemical element and doesn't substantially form chemic compounds. The density and viscosity of helium vapour are very low. The thermic conductivity and the caloric content are uncommonly high. Helium tin exist liquefied, but its condensation temperature is the everyman amid all the known substances.

Applications

Helium has many unique backdrop: low humid point, low density, low solubility, high thermal conductivity and inertness, so it is utilize for any application which tin explioit these backdrop. Helium was the commencement gas used for filling balloons and dirigibles. This application goes on in altitude enquiry and for meteorological balloons. The main utilise of helium is equally an inert protection gas in autogenous welding. Its biggest potential is institute in applications at very depression temperatures. Helium is the but libation which is capable of reaching temperatures lower than fifteen 1000 (-434ºF). The principal application of ultralow temperature is in the development of the superconductivity state, in which the resistance to the electricity flux is almost zero. Other applications are its apply as pressurizing gas in liquid propellants for rockets, in helium-oxygen mixtures for defined, every bit working fluid in nuclear reactors cooled downward by gas and every bit gas carrier in chemical analysis by gas chromatography.

Helium in the surround

Helium is the second most abundant element in the known universe, after hydrogen. Helium constitutes the 23% of all elemental matter measured by mass. Helium is formed in The World by natural radioactive decay of heavier elements. About of this helium migrates to the surface and enters the temper. Information technology could be logical to think that the helium concentration in the atmosphere was higher than information technology is (five,25 parts per one thousand thousand at sea level). Notwithstanding, its low molecular weight allows it to escape to space at the same charge per unit of its formation. There is an about 1000 km layer in the heterosphere at 600 miles where helium is the dominant gas (although the total pressure is very low). Natural gases contain college helium concentrations than the atmosphere.
Helium is the 71st most arable chemical element in the Earth'due south crust where it is found in 8 parts per billion (10⁹).

Health furnishings of helium

Effects of exposure: The substance tin can exist captivated into the body by inhalation. Inhalation: High voice. Dizziness. Dullness. Headache. Suffocation. Skin: on contact with liquid: frostbite. Optics: on contact with liquid: frostbite. Inhalation hazard: On loss of containment this gas tin cause suffocation by lowering the oxygen content of the air in confined areas. Check oxygen content before inbound expanse.
Neutral helium at standard conditions is non-toxic, plays no biological role and is found in trace amounts in man blood.