Helium is a chemical element with the symbol He and atomic number 2.
It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table.
It's boiling and melting point are the lowest among all the elements.
Symbol: He
Atomic number: 2
Atomic mass: 4.002602 u
Electrons per shell: 2
Electron configuration: 1s2
Boiling point: -268.9 °C
Discoverers: Pierre Janssen, William Ramsay, Norman Lockyer, Per Teodor Cleve
List of facts
Helium is a chemical element with the symbol He
Helium is named for the Greek Titan of the Sun.
Helium is the atomic number 2
Helium is present in our Earth's atmosphere at approximately 0.0005% by volume.
It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table.
It's boiling and melting point are the lowest among all the elements.
It is the second lightest and second most abundant element in the observable universe
The first evidence of helium was observed on August 18, 1868, as a bright yellow line with a wavelength of 587.49 nanometers in the spectrum of the chromosphere of the Sun.
In 1895, Sir William Ramsey found helium on Earth when he experimented with combining the uraninite material cleveite with mineral acids.
At the same time, N. A. Langley and P. T. Cleve discovered helium independently and are also credited with helium's discovery.
Helium is the second least reactive noble gas after neon
When ionized, Helium gives out a pale-yellow glow. It’s was this yellow spectra line that led to its discovery.
Unlike any other element, helium will remain liquid down to absolute zero at normal pressures.
There are nine known isotopes of helium, but only helium-3 and helium-4 are stable.
Helium atoms also fuse to form carbon, silicon, and oxygen.
helium-4 accounts for nearly all of the natural helium.
Helium is widely used in cryogenic research because its boiling point is near absolute zero
A mixture of helium and oxygen is used as an artificial atmosphere for divers and others working under pressure.
Helium is used for filling balloons.
Helium is extracted from natural gases through fractional distillation, a process that is used to isolate helium from other elements.
In the United States, most helium is extracted from the natural gas of the Hugoton and nearby gas fields in Kansas, Oklahoma, and the Panhandle Field in Texas
78% of helium is produced in the United States, 10% from Algeria, and most of the remainder from Russia, Poland and Qatar.
In its liquid form, helium is used as a coolant in superconducting electromagnets
By 2013, helium production in Qatar had increased Qatar's fraction of world helium production to 25% and made it the second largest exporter after the USA
An estimated 54 billion cubic feet deposit of helium was found in Tanzania in 2016.
A large-scale helium plant was opened in Ningxia, China in 2020
the Saturn V rocket used in the Apollo program needed about 13 million cubic feet of helium to launch
Helium is also used in some hard disk drives
In arc welding processes that involve materials that are weakened by nitrogen at welding temperatures, Helium serves as the shielding gas.
In the growing of germanium and silicon crystals as well as the production of titanium and zirconium, helium serves as the protective gas.
Helium is a commonly used carrier gas for gas chromatography.
The age of rocks and minerals that contain uranium and thorium can be estimated by measuring the level of helium with a process known as helium dating
Helium-3 is abundant on the moon.
Neutral helium at standard conditions is non-toxic, plays no biological role, and is found in trace amounts in human blood.
Helium was approved for medical use in the United States in April 2020 for humans and animals.
The most common isotope of helium in the universe is helium-4, the vast majority of which was formed during the Big Bang.
Large amounts of new helium are created by the nuclear fusion of hydrogen in stars.
helium once released into the atmosphere, it promptly escapes into space
As of 2012, the United States National Helium Reserve accounted for 30 percent of the world's helium
Melting point 0.95 K (−272.20 °C, −457.96 °F) (at 2.5 MPa)
Boiling point 4.222 K (−268.928 °C, −452.070 °F)
Density (at STP) 0.1786 g/L
when liquid (at m.p.) 0.145 g/cm3
when liquid (at b.p.) 0.125 g/cm3
Triple point 2.177 K, 5.043 kPa
Critical point 5.1953 K, 0.22746 MPa
Heat of fusion 0.0138 kJ/mol
Heat of vaporization 0.0829 kJ/mol
Molar heat capacity 20.78 J/(mol·K)[2]
