Realizing that related elements likely existed, he then found neon, krypton and xenon in quick succession. Because argon is inert, it is used in industrial processes that require a non-reactive atmosphere.
Examples, according to gas supply company Praxair , include welding specialty alloys and producing semiconductor wafers. Argon is also a good insulator, so it's often pumped into deep-sea diving dry suits to keep the diver warm.
Another use for argon is in historical preservation. The gas is pumped around important documents such as a map of the world dating back to in the Library of Congress, and a copy of the Magna Carta held by the U.
National Archives. Unlike reactive oxygen, the argon doesn't degrade the paper or ink on delicate documents. For many years, the noble gas xenon has been researched as a treatment for brain injuries. Xenon, however, is expensive, leading researchers to turn to its noble gas cousin, argon, as a potential alternative. The research field is still young, but experiments in cell cultures and in animals suggest that argon could one day be used to limit brain damage after traumatic injuries or oxygen deprivation.
One review published in the journal Medical Gas Research in February found that in most cases, argon treatment reduces brain cell death by significant amounts — 15 to 25 percent, said Derek Nowrangi, one of the paper's authors and a doctoral student at the Loma Linda University School of Medicine in California.
No one yet understands why argon has this effect. Brain cells communicate with the use of chemicals called neurotransmitters and with neuroreceptors that fit together like lock and key.
Most likely, Nowrangi told Live Science, the gas acts on these neuroreceptors, specifically the NMDA receptor which stands for N-methyl-D-aspartate for the neurotransmitter it receives or the GABA receptor which stands for gamma-aminobutyric acid.
Somehow, when taken up by these receptors, the argon seems to act to prevent cells from self-destructing in response to brain damage. In research, argon gas is either directly applied to cells in a culture dish that are under stress, such as an oxygen- and glucose-deprived environment, or given mixed with oxygen in a facemask for animal studies. Researchers then quantify the number of cells that died with and without argon treatment.
As research on argon picks up, it's more likely that human trials will begin, Nowrangi said. But there are caveats: Some studies find mixed results or negative effects to argon treatment. Each allotrope has different physical properties. For more information on the Visual Elements image see the Uses and properties section below. Group A vertical column in the periodic table. Members of a group typically have similar properties and electron configurations in their outer shell.
Period A horizontal row in the periodic table. The atomic number of each element increases by one, reading from left to right. Block Elements are organised into blocks by the orbital type in which the outer electrons are found.
These blocks are named for the characteristic spectra they produce: sharp s , principal p , diffuse d , and fundamental f. Atomic number The number of protons in an atom. Electron configuration The arrangements of electrons above the last closed shell noble gas. Melting point The temperature at which the solid—liquid phase change occurs. Boiling point The temperature at which the liquid—gas phase change occurs. Sublimation The transition of a substance directly from the solid to the gas phase without passing through a liquid phase.
Relative atomic mass The mass of an atom relative to that of carbon This is approximately the sum of the number of protons and neutrons in the nucleus.
Where more than one isotope exists, the value given is the abundance weighted average. Isotopes Atoms of the same element with different numbers of neutrons. CAS number The Chemical Abstracts Service registry number is a unique identifier of a particular chemical, designed to prevent confusion arising from different languages and naming systems.
Murray Robertson is the artist behind the images which make up Visual Elements. This is where the artist explains his interpretation of the element and the science behind the picture. Where the element is most commonly found in nature, and how it is sourced commercially. Atomic radius, non-bonded Half of the distance between two unbonded atoms of the same element when the electrostatic forces are balanced. These values were determined using several different methods.
Covalent radius Half of the distance between two atoms within a single covalent bond. Values are given for typical oxidation number and coordination. Electron affinity The energy released when an electron is added to the neutral atom and a negative ion is formed. Electronegativity Pauling scale The tendency of an atom to attract electrons towards itself, expressed on a relative scale.
First ionisation energy The minimum energy required to remove an electron from a neutral atom in its ground state. The oxidation state of an atom is a measure of the degree of oxidation of an atom.
It is defined as being the charge that an atom would have if all bonds were ionic. Uncombined elements have an oxidation state of 0. The sum of the oxidation states within a compound or ion must equal the overall charge. Data for this section been provided by the British Geological Survey.
An integrated supply risk index from 1 very low risk to 10 very high risk. This is calculated by combining the scores for crustal abundance, reserve distribution, production concentration, substitutability, recycling rate and political stability scores. The percentage of a commodity which is recycled.
A higher recycling rate may reduce risk to supply. The availability of suitable substitutes for a given commodity. The percentage of an element produced in the top producing country.
The higher the value, the larger risk there is to supply. The percentage of the world reserves located in the country with the largest reserves. A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators. A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. Specific heat capacity is the amount of energy needed to change the temperature of a kilogram of a substance by 1 K.
A measure of the stiffness of a substance. It provides a measure of how difficult it is to extend a material, with a value given by the ratio of tensile strength to tensile strain. A measure of how difficult it is to deform a material. It is given by the ratio of the shear stress to the shear strain. A measure of how difficult it is to compress a substance.
It is given by the ratio of the pressure on a body to the fractional decrease in volume. A measure of the propensity of a substance to evaporate. It is defined as the equilibrium pressure exerted by the gas produced above a substance in a closed system. This Site has been carefully prepared for your visit, and we ask you to honour and agree to the following terms and conditions when using this Site.
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Jump to main content. Periodic Table. Glossary Allotropes Some elements exist in several different structural forms, called allotropes. Allotropes -. Glossary Group A vertical column in the periodic table. Fact box. Glossary Image explanation Murray Robertson is the artist behind the images which make up Visual Elements. Appearance The description of the element in its natural form.
Biological role The role of the element in humans, animals and plants. 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.
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