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. 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. A colourless, odourless gas. Neon will not react with any other substance. In a vacuum discharge tube neon glows a reddish orange colour. Only the red signs actually contain pure neon. Others contain different gases to give different colours. Neon is also used to make high-voltage indicators and switching gear, lightning arresters, diving equipment and lasers.
Liquid neon is an important cryogenic refrigerant. It has over 40 times more refrigerating capacity per unit volume than liquid helium, and more than 3 times that of liquid hydrogen. Biological role.
Moore tubes used nitrogen or carbon dioxide as the luminous gas. This was partly due to the scarcity of neon, but also because, when a current is passed through carbon dioxide, it emits the sort of white glow that could be used to light a room.
In Claude demonstrated the modern neon light as we know it. He intended it for domestic use, but homeowners were put off by the red colour. However, the neon light was embraced by the advertising world, who saw its potential for creating outlandish displays. There are actually two different kinds of neon lights. It will either use a different noble gas, or else some kind of coloured fluorescent lighting. The other kind of neon lights are neon glow lamps.
These tiny lamps operate at around — volts. Before the mass implementation of light emitting diodes LEDs they were widely used in circuit testing equipment and as power-on indicators. Ramsay named the newfound element neon based on the Greek word neos , which means new. The most common use of the gas is in neon signs, which have a century-long history. First developed by French engineer Georges Claude in , neon lights create light by applying electricity to neon or argon in a sealed glass tube.
Argon makes blue light, and neon makes the clear orange-red that is familiar in neon signs, said Bill Concannon, a neon-sign artist and owner of Aargon Neon, a sign shop in Crockett, California. Other colors are created by using a variety of other gases, such as argon, mercury, helium, krypton and xenon, according to the Edison Tech Center.
Today, the majority of the lights you see in many places, such as on the Las Vegas strip, are made from mercury and argon and colored with phosphors. Neon lights, also known as cold cathode fluorescent lamps CCFL , work when electrodes on each end of a vacuum tube filled with neon or other fluorescing gas are subjected to an alternating current, according to the Edison Tech Center. The current ionizes the atoms causing the tube to be filled with free electrons.
As the ionized atoms recapture their electrons to become neutral, visible light is released which gives the CCFL signs their colored glow. Astronomers are studying the neon ratios in the sun to better understand not only our own star but also other stars in our universe. Two studies Young and Brooks, et al. According to Young, the ratio of magnesium to neon is important for better understanding the ionization potentials in the solar atmosphere while the ratio of oxygen to neon could potentially aid in determining the amount of neon in the photosphere of the sun.
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