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.
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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. An image reflecting the importance of boron as an essential mineral for plants. Amorphous boron is used as a rocket fuel igniter and in pyrotechnic flares. It gives the flares a distinctive green colour.
The most important compounds of boron are boric or boracic acid, borax sodium borate and boric oxide. These can be found in eye drops, mild antiseptics, washing powders and tile glazes. Boron filaments are used in the aerospace industry because of their high-strength and lightweight. Boron forms several commercially important compounds. Large amounts of this compound are used in the manufacture of fiberglass insulation and sodium perborate bleach.
The second most important compound is boric acid H 3 BO 3 , which is used to manufacture textile fiberglass and is used in cellulose insulation as a flame retardant. Borax is used in laundry products and as a mild antiseptic.
Borax is also a key ingredient in a substance known as Oobleck , a strange material 6th grade students experiment with while participating in Jefferson Lab's BEAMS program. Other boron compounds are used to make borosilicate glasses, enamels for covering steel and as a potential medicine for treating arthritis. Compounds of boron, particularly borax , have been used by humans for thousands of years, according to Chemicool. Borax sodium tetraborate forms naturally during the evaporation of some salt lakes, according to AZoM , an online reference site for the engineering and materials science community.
In the eighth century A. These early uses echo in borax's and ultimately, boron's name: The word is from the Arabic "buraq," or white. However, the element itself was not extracted until , according to the Royal Society of Chemistry. Even then, chemists weren't able to get a pure form of boron. That goal was not reached until a century later, in , when U.
As part of borax, boron is a very common household element that is found in many detergents. Pro tip: A borax-sugar solution will also kill ants! It's also in the recipe for the science-fair goop oobleck, a liquid with some very strange properties. A mixture of borax solution and liquid glue creates a substance that is liquid when it is poured but solid when it is under pressure. Oobleck is a non-Newtonian fluid , which means that its viscosity depends on the shear force applied to it.
The glue and oobleck join up to create long, thin polymer molecules. A "tap" or strong pressure forces the molecules in the fluid together, creating a solid. A slow movement like pouring or a gentle poke allows the molecules to flow against one another, making the oobleck behave like a fluid. The same concept is what makes Silly Putty both able to flow and bounce. Oobleck can also be made with a mixture of cornstarch and water. But boron isn't all fun and games. The isotope boron happens to be excellent at absorbing neutrons.
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