Shield gases protect the metal during welding to keep it from being oxidized. Argon is highly inert, meaning it doesn't react with other chemicals, so it's an effective shield gas in welding.
Its inert nature also makes argon very useful for production of titanium and other reactive materials like silicon, since these tend to oxidize rapidly if not protected from the surrounding air. Incandescent light bulbs typically contain argon since this inert gas will not react with the filament even at very high temperatures. Some double-paned glass windows employ argon as an insulator between the two panes of glass since it's a very poor conductor of heat.
Thanks to its nonreactive properties and its value as an insulator, argon is sometimes also used to inflate dry suits for scuba diving. Scientists studying Earth's climate need to reconstruct how the planet's climate has changed over the millennia to get a better sense of future trends. Ice cores are a valuable tool for this kind of research.
Scientists drill down into an ice sheet in Antarctica or Greenland, extract a cylindrical sample from the sheet and measure concentrations of nitrogen, argon and other gases trapped in the ice. The ratio of isotopes of argon can help scientists determine average temperature data over a given time period.
Based in San Diego, John Brennan has been writing about science and the environment since The Martian atmosphere in contrast contains 1. World production exceeds Argon does not react with the filament in a lightbulb even under high temperatures, so is used in lighting and in other cases where diatomic nitrogen is an unsuitable semi- inert gas.
Argon is perticularly important for the metal industry, being used as an inert gas shield in arc welding and cutting. Other uses incude non-reactive blanket in the manufacture of titanium and other reactive elements and as a protective atmosphere for growing silicon and germanium crystals.
Argon has been used for a number of applications, primarily ice coring. It has also been used for ground water dating. Argon is also used in technical SCUBA diving to inflate the drysuit, due to its nonreactive, heat isolating effect.
Argon as the gap between the panes of glass provides better insulation because it is a poorer conductor of heat than ordinary air. The most exotic use of argon is in the tyre of luxury cars. In earth's atmosphere, Ar is made by cosmic ray activity, primarily with Ar In the subsurface environment, it is also produced through neutron-capture by K or alpha emission by calcium. Argon is produced from the decay of calcium, the result of subsurface nuclear explosions. It has a half-life of 35 days.
Argon is present in some potassium minerals because of radiactive decay of the isotope potassium Routes of exposure: The substance can be absorbed into the body by inhalation. Inhalation risk: On loss of containment this liquid evaporates very quickly causing supersaturation of the air with serious risk of suffocation when in confined areas. Effects of exposure: Inhalation: Dizziness. Natural abundance Where the element is most commonly found in nature, and how it is sourced commercially.
Uses and properties. Image explanation. The image reflects the use of the element in the welding industry. Argon provides an inert atmosphere in which welded metals will not oxidise. Argon is a colourless, odourless gas that is totally inert to other substances.
Argon is often used when an inert atmosphere is needed. It is used in this way for the production of titanium and other reactive elements. It is also used by welders to protect the weld area and in incandescent light bulbs to stop oxygen from corroding the filament. Argon is used in fluorescent tubes and low-energy light bulbs. A low-energy light bulb often contains argon gas and mercury. When it is switched on an electric discharge passes through the gas, generating UV light.
The coating on the inside surface of the bulb is activated by the UV light and it glows brightly. Double-glazed windows use argon to fill the space between the panes. The tyres of luxury cars can contain argon to protect the rubber and reduce road noise. Biological role. Natural abundance. Argon makes up 0. Levels have gradually increased since the Earth was formed because radioactive potassium turns into argon as it decays. Argon is obtained commercially by the distillation of liquid air.
Help text not available for this section currently. Elements and Periodic Table History. Argon was discovered as a result of trying to explain why the density of nitrogen extracted from air differed from that obtained by the decomposition of ammonia. Ramsay removed all the nitrogen from the gas he had extracted from air, and did this by reacting it with hot magnesium, forming the solid magnesium nitride. He was then left with a gas that would not react and when he examined its spectrum he saw new groups of red and green lines, confirming that it was a new element.
Atomic data. Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom. Oxidation states and isotopes.
Glossary Data for this section been provided by the British Geological Survey. Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk. Recycling rate The percentage of a commodity which is recycled.
Substitutability The availability of suitable substitutes for a given commodity. Reserve distribution The percentage of the world reserves located in the country with the largest reserves. Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators. Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators.
Supply risk. Relative supply risk Unknown Crustal abundance ppm 3. Young's modulus A measure of the stiffness of a substance. Shear modulus A measure of how difficult it is to deform a material. Bulk modulus A measure of how difficult it is to compress a substance. Vapour pressure A measure of the propensity of a substance to evaporate. Pressure and temperature data — advanced. Listen to Argon Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry.
Hello, this week the element that's so indolent that scientists at one time thought it wouldn't react with anything, but in the chemical world laziness can have its advantages especially if it's super quiet car tyres or a safe chemical with which to pump up your diving suit that you're after.
Argon's name comes from the Greek word argos meaning lazy and indeed for more than a hundred years after its discovery chemists were unable to get it to combine with any other elements. They made it by condensing a mixture of argon and hydrogen fluoride on to caesium iodide at o C and exposing it to UV light.
On warming above just o C it reverted right back to argon and hydrogen fluoride. And no other process has ever induced argon to react - [a truly lazy element]. There are 50 trillion tonnes of argon swirling around in the Earth's atmosphere and this has slowly built-up over billions of years, almost all coming from the decay of the radioactive isotope potassium which has a half-life of Although argon makes up 0.
The story of its discovery started when Rayleigh found that the nitrogen extracted from the air had a higher density than that made by decomposing ammonia. The difference was small but real.
Ramsay wrote to Rayleigh suggesting that he should look for a heavier gas in the nitrogen got from air, while Rayleigh should look for a lighter gas in that from ammonia. Ramsay removed all the nitrogen from his sample by repeatedly passing it over heated magnesium, with which nitrogen reacts to form magnesium nitride.
He was left with one percent which would not react and found it was denser than nitrogen. Its atomic spectrum showed new red and green lines, confirming it a new element. Although in fact it contained traces of the other noble gases as well.
He didn't realise that he had stumbled on a new gaseous element. Most argon goes to making steel where it is blown through the molten iron, along with oxygen. Argon does the stirring while the oxygen removes carbon as carbon dioxide.
It is also used when air must be excluded to prevent oxidation of hot metals, as in welding aluminium and the production of titanium to exclude air. Welding aluminium is done with an electric arc which requires a flow of argon of at litres per minute.
Atomic energy fuel elements are protected with an argon atmosphere during refining and reprocessing. The ultra-fine metal powders needed to make alloys are produced by directing a jet of liquid argon at a jet of the molten metal. Some smelters prevent toxic metal dusts from escaping to the environment by venting them through an argon plasma torch. For a gas that is chemically lazy argon has proved to be eminently employable.
Illuminated signs glow blue if they contain argon and bright blue if a little mercury vapour is also present. Double glazing is even more efficient if the gap between the two panes of glass is filled with argon rather than just air because argon is a poorer conductor of heat.
Thermal conductivity of argon at room temperature K is For the same reason argon is used to inflate diving suits. Old documents and other things that are susceptible to oxidation can be protected by being stored in an atmosphere of argon. Blue argon lasers are used in surgery to weld arteries, destroy tumors and correct eye defects. The most exotic use of argon is in the tyres of luxury cars. Not only does it protect the rubber from attack by oxygen, but it ensures less tyre noise when the car is moving at speed.
Laziness can prove useful in the case of this element. Its high tech uses range from double glazing and laser eye surgery to putting your name in lights. John Emsley unlocking the secrets of the heavier than air noble gas argon. Next week, would you marry this man?
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