Helium

Helium (He) is a chemical element and inert gas belonging to the Periodic Table’s Group 18 (noble gases). Helium is the second lightest element (only hydrogen is lighter), and it is a colourless, odourless, and tasteless gas that turns into a liquid at a temperature of 268.9 degrees Celsius (452 degrees Fahrenheit). Helium has lower boiling and freezing points than any other known substance, making it the most energy-dense element. Helium is the only element that cannot be solidified by sufficient cooling under normal atmospheric pressure; it requires the application of 25 atmospheres of pressure at a temperature of 1 K (272 degrees Celsius or 458 degrees Fahrenheit) in order to convert it to its solid state. 

Helium facts

• Helium has an atomic number of 2, which means that each atom of helium contains two protons. The element’s most abundant isotope has two neutrons, making it the most abundant isotope. It is more energy efficient for each helium atom to have two electrons, which results in a more stable electron shell for the atom.

• Helium has the lowest melting and boiling points of all the elements, and as a result, it can only exist as a gas except in extremely extreme circumstances. Helium is a liquid at absolute zero pressure when under normal pressure. It needs to be pressurised in order to solidify.

• Helium is the second lightest element after hydrogen. Hydrogen is the lightest element, as well as the element with the lowest density. Despite the fact that hydrogen is typically found as a diatomic gas, consisting of two atoms that are bonded together, a single atom of helium has a higher density value than a single atom of hydrogen. This is due to the fact that the most common isotope of hydrogen contains only one proton and no neutrons, whereas each helium atom contains two neutrons in addition to two protons.

• In the universe, helium is the second most abundant element (behind hydrogen) despite the fact that it is much less common on the planet. The element is regarded as a nonrenewable resource on the planet Earth. Helium does not combine with other elements to form compounds, and the free atom is light enough to escape the gravitational pull of the Earth and bleed out through the atmosphere. Some scientists are concerned that we will run out of helium in the near future, or that it will become prohibitively expensive to extract.

• Helium is colourless, odourless, tasteless, non-toxic, and inert. It has no corrosive properties. Helium is the least reactive of all the elements, and as a result, it does not combine with other elements to form compounds under normal circumstances. It would have to be ionised or pressurised in order to form a bond with another element, however. The disodium helide (HeNa2), the silica crystobalite He II (SiO2He), dihelium arsenolite (AsO6-2He), and the neon helide (NeHe2) are all possible under high pressure.

• The majority of helium is obtained through the extraction of the element from natural gas. Helium is used in a variety of applications, including party balloons, as a protective inert atmosphere for chemistry storage and reactions, and to cool superconducting magnets used in NMR spectrometers and magnetic resonance imaging machines.

• Helium is the second least reactive noble gas in terms of reactivity (after neon). It is considered to be the real gas that behaves the most closely to the behaviour of an ideal gas in terms of temperature and pressure.

• Under standard conditions, helium is a monatomic gas. In other words, helium is found in the form of single atoms of the chemical element helium.

The sound of a person’s voice is temporarily altered when they inhale helium. Although many people believe that inhaling helium makes a person’s voice sound higher, this is not the case. In spite of the fact that helium is non-toxic, breathing it can result in asphyxiation due to a lack of oxygen.

• The discovery of helium came about as a result of the observation of a yellow spectral line from the sun’s rays. In Greek mythology, Helios (the Sun) is credited with giving the element its name.

Production as well as applications

In order to separate helium gas (98.2 percent pure) from natural gas, the other components must be liquefied at extremely low temperatures and under extremely high pressures. In the presence of other gases, adsorption on cooled, activated charcoal results in the production of 99.995 percent pure helium. Several kilogrammes of helium are produced by large-scale liquefaction of air; the amount of helium produced from 1,000 tonnes (900 metric tonnes) of air is approximately 112 cubic feet (3.17 cubic metres), when measured at room temperature and normal atmospheric pressure.

The gas helium is used in a variety of applications, including welding metals such as aluminium, rocket propulsion (to pressurise fuel tanks, particularly those containing liquid hydrogen, because only helium remains a gas at liquid-hydrogen temperatures), weather forecasting (as a lifting gas for instrument-carrying balloons), cryonics (to cool down liquid helium, which is the coldest substance on the planet), and extreme high-pressure breathing operations (mixed with oxygen, as in scuba diving and caisson work, especially because of its low solubility in the bloodstream). Helium content in meteorites and rocks has been determined as a method of dating the formation of the planets.

Conclusion

Helium (He) is a chemical element and inert gas belonging to the Periodic Table’s Group 18 (noble gases). Helium is the second lightest element (only hydrogen is lighter), and it is a colourless, odourless, and tasteless gas that turns into a liquid at a temperature of 268.9 degrees Celsius.The element helium was discovered in the gaseous atmosphere surrounding the Sun by the French astronomer Pierre Janssen in 1868.Helium has the lowest melting and boiling points of all the elements, and as a result, it can only exist as a gas except in extremely extreme circumstances. Helium is a liquid at absolute zero pressure when under normal pressure. It needs to be pressurised in order to solidify.The gas helium is used in a variety of applications, including welding metals such as aluminium, rocket propulsion (to pressurise fuel tanks, particularly those containing liquid hydrogen.