HELIUMHELIUM (Greek helios, "sun"), symbol He, inert, colorless, odorlessgaseous element. In group 18 (or VIIIa) of the periodic table.
Heliumis one of the noble gases. The atomic number of helium is 2.
Helium has the distinction of being the only element discovered outsideof Earth prior to finding it within our planet.
The gas was first isolated from terrestrial sources in 1895 by theBritish chemist Sir William Ramsay, who discovered it in cleveite, a uranium-bearingmineral.
In 1907 the British physicist Sir Ernest Rutherford showed that alphaparticles are the nuclei of helium atoms, which later investigation confirmed.
Properties and Occurrence
Helium has monatomic molecules, and is the lightest of all gases excepthydrogen. The atomic weight of helium is 4.003.Helium, like theother noble gases, is chemically inert. Its single electron shell isfilled, making possible reactions with other elements extremely difficultand the resulting compounds quite unstable.
Helium is the most difficult of all gases toliquefy and is impossible to solidify at normal atmospheric pressures.These properties make liquid helium extremely useful as a refrigerant andfor experimental work in producing and measuring temperatures close toabsolute zero. Liquid helium can be cooled almost to absolute zero atnormal pressure by rapid removal of the vapor above the liquid. Ithas no freezing point, and its viscosity is apparently zero; it passesreadily through minute cracks and pores and will even creep up the sidesand over the lip of a container.
Helium is the second most abundantelement in the universe, after hydrogen. About 1 part per millionof atmospheric helium consists of helium-3, now thought to be a productof the decay of tritium, a radioactive hydrogen isotope of mass 3. Thecommon helium isotope, helium-4, probably comes from radioactive alphaemitters in rocks. Natural gas, which contains an average of 0.4 percenthelium, is the major commercial source of helium.
Uses
Because it is noncombustible, helium is preferred to hydrogen as thelifting gas in lighter-than-air balloons; it has 92 percent of the liftingpower of hydrogen, although it weighs twice as much. Helium is used topressurize and stiffen the structure of rockets before takeoff and to pressurizethe tanks of liquid hydrogen or other fuel in order to force fuel intothe rocket engines. It is useful for this application because it remainsa gas even at the low temperature of liquid hydrogen. A potential use ofhelium is as a heat-transfer medium in nuclear reactors because it remainschemically inert and nonradioactive under the conditions that exist withinthe reactors.
Helium is used in inert-gas arc welding for lightmetals such as aluminum and magnesium alloys that might otherwise oxidize;the helium protects heated parts from attack by air. Helium is used inplace of nitrogen as part of the synthetic atmosphere breathed by deep-seadivers, caisson workers, and others, because it reduces susceptibilityto the bends. This synthetic atmosphere is also used in medicine to relievesufferers of respiratory difficulties because helium moves more easilythan nitrogen through constricted respiratory passages. Helium is transportedas a gas in small quantities, compressed in heavy steel cylinders. Largeramounts of helium can be shipped as a liquid in insulated containers, thussaving shipping costs.
"Helium," Microsoft(R) Encarta(R) 96 Encyclopedia. (c) 1993-1995 MicrosoftCorporation. All rights reserved. (c) Funk & Wagnalls Corporation.All rights reserved.
FAQs
Helium is a super light gas which can make your vocal cords vibrate at a much faster rate, producing a high-pitched tone. You can inhale helium directly from a balloon for a few seconds and then say something funny to enjoy the effects!
What is the helium party trick? ›
The party trick of inhaling a balloon full of helium to change your voice is dangerous and must be discouraged at all times as it displaces a persons supply of oxygen in the blood stream and may cause dizziness, unconsciousness and possibly death. Inhaling helium is like Russian Roulette.
Can we run out of helium? ›
As helium is a non-renewable resource, the Earth is certainly running out of it. Why is the world running out of helium? Helium is the only element on the periodic table which is a non-renewable resource on Earth.
Can you get 100% helium? ›
Some disposable tanks have as much as 20 percent air added to them. Bargain Balloons has tested the float times of disposable tanks and on average it is much lower. It is so much lower, that some customers even think the balloons used are dective or poor quality. A helium tank never contains 100 percent helium.
What makes your voice deep like helium? ›
Deep Voice Gas - Sulfur Hexafluoride.
Do foil balloons take helium? ›
Foil Balloons - do I fill with air or helium? Some foil balloons are air-fill only and this information is on each item description. Most foil balloons that can be filled with helium can also be filled with air but of course wont float To fill a balloon with air insert a straw into the valve and blow into it.
How long does helium affect your voice? ›
If you've ever breathed helium and heard the sound of your voice, you've probably noticed that the effect wears off quickly. That's because the effect only lasts as long as there's helium around your vocal cords. As soon as regular air replaces the helium, your voice returns to normal.
What will replace helium? ›
Argon can be used instead of Helium and is favoured for some metals. Helium is used for many lighter-than-air applications, and Hydrogen is a possible substitute for many where the flammability of Hydrogen is not a concern.
Will helium be gone in 15 years? ›
Once the gas leaks into the atmosphere, it is light enough to escape the Earth's gravitational field so it bleeds off into space, never to return. We may run out of helium within 25–30 years because it's being consumed so freely.
Is the Earth leaking helium? ›
Helium inherited from the solar nebula likely became locked in Earth's core as the planet formed, making the core a reservoir of noble gases. As helium-3 leaked from the core, it ascended to the surface through the mantle in the form of magma plumes that eventually erupted on Baffin Island.
According to NBC News, scientists estimate there is enough helium left for just 100-200 years at the rate of our consumption. It's a nonrenewable resource, so getting to where it's needed most is important. But as supply decreases and demand increases, prices skyrocket.
What is the rarest helium? ›
One of the rarest gasses, helium-3 is stable, inert, nontoxic and nonflammable. Helium-3 has a wide range of applications. It is an essential molecule for neutron detection, dilution refrigerators, ultra low temperature physics research and aneutronic fusion.
What is cheaper than helium? ›
Although both gases have lightweight natures, hydrogen offers many benefits over helium. Hydrogen is better if you require a more substantial lift for your balloons as it is lighter than helium. It is also much easier to make than helium, making it the cheaper solution to your balloon needs.
Does laughing gas change your voice? ›
As nitrous oxide is often called “laughing gas”, some patients will feel giggly when the gas mixture takes effect. Moreover, your voice may temporarily change during the administration of nitrous oxide since vocal cords are affected by nitrous oxide.
Is helium voice temporary? ›
When we inhale helium, it changes the resonant frequency of our vocal cords, making our voices sound higher. However, the effect is only temporary because as we exhale, the helium is quickly replaced by the denser air, returning our voices to their normal pitch.
