what is helium used for?

Answer 1

(m)

Helium gas is much lighter than air, and has the advantage over hydrogen in that it isn't inflammable at all! If there were a book about Helium Chemistry it would be a very thin volume as helium forms no compounds and doesn't react with any other elements. It's an inert monatomic gas. So it has physics, but no chemistry!

Helium becomes liquid at about 4 Kelvin (minus 269 Celsius). Solid helium exists at even lower temperatures but not at atmospheric pressure. It has to be twenty atmospheres to be solid.

Helium gas is used for balloons, blimps, airships, and for breathing in to make a squeaky voice. (this practice, of breathing helium so as to increase the pitch of your voice so you sound like it's been sampled and increased in speed/pitch is always advised against because of the risk of asphyxiation! However, if you were going to do the trick you'd have to do it with some friends present to show off to, so it would not be as dangerous as the "safe" lobby would suggest). It's also possible to safely breathe Heliox, a diving-gas mixture of helium and oxygen, which saves divers from the horrors of The Bends but has a curious side-effect of the alteration of the vocals. Also, helium conducts heat much better than the more usual Nitrogen in air. Therefore divers using heliox have to have their cylinders warmed up to avoid hypothermia.

Liquid Helium can be used for a variety of cryogenic purposes. It's quite expensive but at that temperature (within four degrees of absolute zero) it's quite useful. Helium3 is a superfluid and behaves in some very odd ways!

Answer 2

The uses of helium depend either on its small atomic mass, or on its chemical inertness.
Helium and argon are used in welding to shield the hot metal from the atmosphere, especially in the case of reactive metals.
Helium is used for leak detection in vacuum systems. The gas is blown around likely leak sources, and will diffuse much more rapidly than air through even the smallest opening. The helium is easily detected by an ionization gauge or other means, signalling the presence of a leak. The rapid diffusion makes helium a good carrier gas for gas chromatography. Helium is also used as a driver gas in hypersonic wind tunnels. The high thermal conductivity, and its zero neutron capture cross section, make helium a good coolant in gas-cooled nuclear reactors, though its low density works against it.
Helium gained fame as a lifting gas, and we have seen that this spurred the large-scale production and conservation of the gas, in spite of its inherent rarity. We have already remarked that it is nearly as effective as hydrogen in this respect, as 25 is to 27. The net lift of a balloon is the weight of the air displaced, less the weight of the balloon, lifting gas and ballast. All balloons using hydrogen or helium are strongly affected by the rapid diffusion of these gases, which soon leads to a decrease in lift, which is compensated by throwing ballast overboard. Incidentally, the lifting gas is contained in separate bags like the compartments of a ship, so that the compromise of one is not the loss of all. The use of helium in small balloons instead of hydrogen seems to be a frivolous waste of a valuable substance. Of course, the reason it is used is the elimination of the hazards of hydrogen combustion, perhaps more in the gas sources than in the actual balloon. If the predictions of a "hydrogen economy" do indeed come true, we will hear more about the dangers of hydrogen. All the problems of working with helium arise with hydrogen as well, with the added excitement of explosion.
A discharge through a mixture of helium and neon creates a population inversion in the neon that can be used in a laser.

Answer 3

Helium is a colorless, odorless, tasteless chemical element,with the symbol He, and atomic number 2, the least reactive of the nearly inert noble gas elements. Its boiling and melting points are the lowest among the elements; except in extreme conditions, it exists only as a gas. At temperatures near absolute zero and standard pressure, helium exists as a superfluid, a nearly frictionless phase of matter with unusual properties.

Helium is the second lightest and also the second most abundant element in the universe, after hydrogen in both cases. It was created during big bang nucleosynthesis and to a lesser extent from nuclear fusion of hydrogen in stars. First detected in 1868 by French astronomer Pierre Janssen as an unknown yellow spectral line signature in the light of a solar eclipse, helium was separately identified as a new element later that year by English astronomer Norman Lockyer.

On Earth, helium is relatively rare, and was not detected until 1895 in mineral samples. It is primarily a product of the radioactive decay of much heavier elements, which emit helium nuclei called alpha particles. Its presence in natural gas, the only place it is found in significant amounts, was identified in 1905. Commercially it is extracted at low temperatures from natural gas by fractional distillation. Natural gas from different wells on different continents varies greatly in helium gas content.

USES OF HELIUM:

-Helium is used in cryogenics(a branch of physics (or engineering) that studies the production of very low temperatures (below –150 °C, –238 °F or 123 K) and the behavior of materials at those temperatures.)

-as a deep-sea breathing gas,

-for inflating balloons and airships,

-and as a protective gas for many industrial purposes, such as arc welding.

-Inhaling a small amount of the gas temporarily changes the timbre of a person's voice; however, caution must be exercised as helium is an asphyxiant.(Causing a condition of severely deficient supply of oxygen to the body that arises from being unable to breathe normally).

Answer 4

Ultra pure helium can be used for cooling superconducting magnet, such as in a MRI machine and High Grade Magnetic Separation (HGMS). The liquid hydrogen is used to cool the superconducting coil to produce zero resistance. When you pass an electric current through the coil you can produce a very strong magnetic field. I have used HGMS in a passed job and the coil temperature must be below 40Deg.K(-233Deg.C.) or resistance will be produced in the coil and a magnetic field cannot be induced. The helium is used as a coolant to conduct heat away from the superconducting coil.

Answer 5

The following uses for helium are gathered from a number of sources as well as from anecdotal comments. I'd be delighted to receive corrections as well as additional referenced uses (please use the feedback mechanism to add uses).

filling balloons (blimps) as it is a much safer gas than hydrogen
widely used as an inert gas shield for arc welding in countries where helium is cheaper than argon
protective gas in growing silicon and germanium crystals, and in titanium and zirconium production
cooling medium for nuclear reactors
a mixture of 80% helium and 20% oxygen is used as an artificial atmosphere for divers and others working under pressure
cryogenic applications
as a gas for supersonic wind tunnels
a protective gas for semiconductor materials
pressurizing liquid fuel rockets

Answer 6

We use He for our Gas Chromatograph (GC). Last time I tried to speak after breathing He I took a deep breath of it and nearly passed out (unconscious, I could potentially fall and break my head open). This was decades ago, the guys I was with said as I slowly took in the He I quickly turned blue from the neck up. I didn't need those brain cells anyway...but my voice didn't sound any different to me!

Answer 7

Filling up balloons, create low temperature, in welding, and for magnets.

Answer 8

To make balloons float

Answer 9

Making my voice sound funny when i inhale the contents of one of my kids balloons!

Answer 10

Balloons...or to sound like one of the Chipmunks (Alvin, Simon, Theodore!!)...