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. Copyright of and ownership in the Images reside with Murray Robertson.
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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. Inhalation in excessive concentrations can result in dizziness, nausea, vomiting, loss of consciousness, and death.
Death may result from errors in judgment, confusion, or loss of consciousness which prevent self-rescue. At low oxygen concentrations, unconsciousness and death may occur in seconds without warning.
The effect of simple asphyxiant gases is proportional to the extent to which they diminish the amount partial pressure of oxygen in the air that is breathed. Symptoms: The first symptoms produced by a simple asphyxiant are rapid respirations and air hunger. Mental alertness is diminished and muscular coordination is impaired.
Later judgment becomes faulty and all sensations are depressed. Emotional instability often results and fatigue occurs rapidly. As the asphyxia progresses, there may be nausea and vomiting, prostration and loss of consciousness, and finally convulsions, deep coma and death. No adverse environmental consequences are expected. Argon gas occurs naturally in the environment.
The gas will dissipate rapidly in well ventilated areas. The effects of argon on plants or animals is not currently known. These holes are needed in production — one for pumping argon in, the other to allow air to be pushed out as the gas comes in.
This noble gas may be used as a dry suit insulation for cold-water diving. This is because argon is inert and possesses low thermal conductivity. It can also be used in its argox form, which is the informal name given to a scuba diving breathing gas made of argon and oxygen. However, this application is fairly rare.
The following list includes more uses for this noble gas, although it is by no means comprehensive:. Other inert gases can fulfil some of the functions of argon — however, argon is especially attractive because of how cost-effective and abundant it is. At Adams Gas, we stock a range of argon gas supplies for your use.
Our disposable gas cylinders are a cost-effective alternative to stationary, industrial size gas cylinders, and they are manufactured to the highest quality. For our trade customers, we specifically introduced our rent-free pure argon gas, aimed at businesses who go through a 50L cylinder every 3 months.
If you would like to know any further information about our products and services, please do not hesitate to get in touch with us today by calling or emailing sales adamsgas. 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. In one, Nowrangi said, the brain as a whole seemed protected by argon, but damage to one area was actually increased with the gas treatment.
This could be because the argon didn't penetrate to that region, or because different brain regions have different cell types and cell densities. Stephanie Pappas is a contributing writer for Live Science covering topics from geoscience to archaeology to the human brain and behavior. A freelancer based in Denver, Colorado, she also regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association.
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