Why is helium chemically inert

The main source of helium is from natural gas, where it is separated out from the other components by fractional distillation.

Helium liquefies at 4. Some materials become superconductors when immersed in liquid helium; in these materials, there is no resistance to the flow of electricity. Superconducting magnets are used for an important medical imaging technology called Magnetic Resonance Imaging MRI , which allows images of tissues and organs to be obtained.

A related technology is used by chemists to obtain information that can be used to deduce the structures of molecules; this technique is called Nuclear Magnetic Resonance NMR ; the two technologies are basically the same, but the term "nuclear" is avoided in the medical application because of its unpleasant associations even though there is no nuclear radiation involved. Helium is also used in blimps, where the combination of being lighter than air and nonflammable makes it much safer than hydrogen as demonstrated in the explosion of the Hindenburg.

It is also used in deep-sea diving, since helium is less soluble in the bloodstream than nitrogen, and reduces the risk of the diver suffering nitrogen narcosis, high pressure nervous syndrome HPNS , or the bends.

Breathing helium gas causes the voice to become higher pitched because helium is less dense than air, changing the frequency of the sound waves generated in the larynx. Neon is a colorless, odorless, unreactive gas which liquefies at Neon was discovered in by Sir William Ramsay see entry on Argon below and his assistant Morris Travers while working with a sample of krypton. The name comes from the Greek word for "new," neos.

It is found in the Earth's crust at a concentration of 70 ppt, making it the 80th most abundant element; it is found in the atmosphere at a concentration of 18 ppm by volume. Neon which is used commercially is extracted from liquid air by fractional distillation. Neon is used primarily in neon lights ; stimulating neon with electricity causes it to emit an intense red light.

Other noble gases are used in "neon lights" as well, to produce different colors. Neon is also used in some underwater breathing mixtures; liquid neon is used in low-temperature cooling.

Argon is a colorless, odorless, unreactive gas which liquefies at Explain why argon, krypton or xenon are used in these lamps. The hot metal wires will burn away if any oxygen from air is present in the lamp. Argon, krypton and xenon are very unreactive.

They replace the air inside the lamp, preventing the metal wire from burning away. Chemical properties of the noble gases Compared to other elements , the noble gases are inert - they are extremely unreactive.

Explaining the inertness of noble gases When elements react, their atoms complete their outer shells by losing, gaining, or sharing electrons. Until now, theory had only posited that helium would form violently reactive ions with hydrogen and merely metastable compounds with that most aggressive of non-metals fluorine. This is, however, a far cry from making helium compounds. This is in many ways the last bastion of inertness that has fallen.

The discovery of the compound is particularly attractive because of the way it was made with the large-scale theoretical search resulting in a single hit for binaries is a sign of the strength of modern theoretical methods. Theory and theorists have come a long way from proving the non-existence of He 2 to proving that of Na 2 He. X Dong et al , Nat.

State of hydrogen predicted to be a room temperature superconductor reportedly seen — but the methods used are being questioned. One chemistry professor received three months for producing the drug in a university lab, while another was acquitted.

Site powered by Webvision Cloud. Skip to main content Skip to navigation. Last year scientists reported producing the compounds—crystals made of sodium and helium atoms—but could not understand how they formed. Now a new team of researchers has offered an explanation: Helium manages to combine with other atoms without making any chemical bonds—that is, without sharing or exchanging any electrons.

The element does this by shielding positively charged atoms from each other, acting as a buffer between their repellent charges. The compounds are stunning because scientists had thought helium extremely unlikely to combine with other atoms. This is because a helium atom is loath to give up its two electrons, which perfectly fill its only electron shell. Every atom has such shells, which hold specific numbers of electrons and structure these negatively charged particles around the atomic nucleus.

Atoms prefer their shells to be totally full, and will bond with other atoms that can take or give an extra particle or two to fill out a shell. Elements with shells that are already full and have no electrons to lend are called noble gases—and helium, the smallest of these, is considered the most inert.