Other uses are as general anaesthetic, xenon 'blue' headlights and fog lights are used on some vehicles and are said to be less tiring on the eyes. They illuminate road signs and markings better than conventional lights. Xenon is a trace gas in the Earth's atmosphere, occurring in 1 part in 20 million. The only commercial source of xenon is from industrial liquid-air plants.
World production is less than 1 tonne per year, although reserved of xenon gas in the atmosphere amount to 2 billion tonnes. Inhalation: This gas is inert and is classified as a simple asphyxiant. 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.
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. Copyright of and ownership in the Images reside with Murray Robertson. The RSC has been granted the sole and exclusive right and licence to produce, publish and further license the Images. The RSC maintains this Site for your information, education, communication, and personal entertainment.
You may browse, download or print out one copy of the material displayed on the Site for your personal, non-commercial, non-public use, but you must retain all copyright and other proprietary notices contained on the materials. You may not further copy, alter, distribute or otherwise use any of the materials from this Site without the advance, written consent of the RSC. The images may not be posted on any website, shared in any disc library, image storage mechanism, network system or similar arrangement.
Pornographic, defamatory, libellous, scandalous, fraudulent, immoral, infringing or otherwise unlawful use of the Images is, of course, prohibited. If you wish to use the Images in a manner not permitted by these terms and conditions please contact the Publishing Services Department by email.
If you are in any doubt, please ask. Commercial use of the Images will be charged at a rate based on the particular use, prices on application. In such cases we would ask you to sign a Visual Elements licence agreement, tailored to the specific use you propose. The RSC makes no representations whatsoever about the suitability of the information contained in the documents and related graphics published on this Site for any purpose.
All such documents and related graphics are provided "as is" without any representation or endorsement made and warranty of any kind, whether expressed or implied, including but not limited to the implied warranties of fitness for a particular purpose, non-infringement, compatibility, security and accuracy.
In no event shall the RSC be liable for any damages including, without limitation, indirect or consequential damages, or any damages whatsoever arising from use or loss of use, data or profits, whether in action of contract, negligence or other tortious action, arising out of or in connection with the use of the material available from this Site. Nor shall the RSC be in any event liable for any damage to your computer equipment or software which may occur on account of your access to or use of the Site, or your downloading of materials, data, text, software, or images from the Site, whether caused by a virus, bug or otherwise.
Jump to main content. Periodic Table. Glossary Allotropes Some elements exist in several different structural forms, called 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. This is usually a tube filled with xenon gas, with electrodes at each end and a metal trigger plate at the middle of the tube. A colourless, odourless gas.
It is very unreactive. Xenon is used in certain specialised light sources. It produces a beautiful blue glow when excited by an electrical discharge. Xenon lamps have applications as high-speed electronic flash bulbs used by photographers, sunbed lamps and bactericidal lamps used in food preparation and processing.
Xenon lamps are also used in ruby lasers. Xenon ion propulsion systems are used by several satellites to keep them in orbit, and in some other spacecraft. Xenon difluoride is used to etch silicon microprocessors. It is also used in the manufacture of 5-fluorouracil, a drug used to treat certain types of cancer. Companies obtain the gas for commercial use from industrial plants that extract the gas from liquid air.
Xenon may also be found in the Earth. For a long time, scientist suspected that 90 percent more of the gas should be found in the Earth's atmosphere, based on their knowledge of other noble gases. Eventually, scientists, including Ma, found evidence that the missing gas may be found at the Earth's core. The extreme temperatures and pressures found in Earth's core may cause xenon to bond with iron and nickel located in the core, storing the gas there.
Xenon creates a blue or lavender glow when subjected to an electrical discharge. Lamps that use xenon illuminate better than conventional lights. For example, stroboscopic lamps, photographic flash lamps, high-intensive arc-lamps for motion picture projection, some lamps used for deep-sea observation, bactericidal lamps, sunbed lamps and high-pressure arc all use this gas.
In fact, you probably see xenon lamps on a regular basis. Some vehicle headlights use xenon. If you see headlights that give off a soft blue glow, they are probably made with xenon.
The gas has other uses, too. It is used in nuclear energy plants and for filling television and radio tubes. Silicon microprocessors are etched with xenon difluoride. Xenon ion propulsion systems keep some satellites and other spacecraft in orbit.
0コメント