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. Discovery date Discovered by Georg Brandt Origin of the name The name is derived from the German word 'kobald', meaning goblin.
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. In the background is some early Chinese porcelain, which used the element cobalt to give it its blue glaze.
A lustrous, silvery-blue metal. It is magnetic. Cobalt, like iron, can be magnetised and so is used to make magnets. It is alloyed with aluminium and nickel to make particularly powerful magnets. Other alloys of cobalt are used in jet turbines and gas turbine generators, where high-temperature strength is important.
Cobalt metal is sometimes used in electroplating because of its attractive appearance, hardness and resistance to corrosion. As a report from the U. Geological Survey explains, DRC has a poor history of government corruption, human rights violations and environmental damage related to cobalt mining.
It's not only human rights groups like Amnesty International that are concerned with unsafe and unethical labor practices related to unregulated "artisanal" cobalt mining in the DRC. The political and environmental instability of DRC means that a huge chunk of the cobalt supply chain is vulnerable to disruption.
If the high-tech economy relies on a steady supply of cobalt, largely to be used in rechargeable batteries, than troubles in the DRC could slow economic growth worldwide. The USGS report also notes that China is the main refiner of cobalt and one of the biggest financial backers of large cobalt mining operations in the DRC. As it stands, the U. Which accounts for the last fact on out list. According to figures from , the United States consumed 10 percent of the world's cobalt while producing less than 1 percent of the global cobalt supply.
Cobalt isn't everywhere, but it also isn't a particularly rare mineral — it ranks 32nd in abundance in the earth's crust. Only two mines in Canada and Morocco can extract pure cobalt ore, while the majority is extracted as a byproduct of copper and nickel mining.
The U. The mining industry also has complained of a slow permitting process to allow for mineral exploration, both onshore and offshore. The Trump administration has directed the Department of Interior to speed up the permitting process in an effort to decrease America's reliance on foreign sources of critical minerals like cobalt.
Despite permitting and geological obstacles, there has been some progress in U. In , the Eagle Mine in Michigan's Upper Peninsula began mining nickel and copper with cobalt and other minerals as a byproduct. And America's first mine dedicated to cobalt is getting ready to go into production in in Idaho.
Cobalt is an essential micronutrient in animal and human diets. Ruminants like cows transform cobalt into cobalamin, also known as vitamin B The food with the highest concentration of cobalt is chocolate!
Cobalt is one of the three ferromagnetic metals, so it is often used in alloys for magnets. When cobalt is alloyed with the other two ferromagnetic elements, iron and nickel, it forms alnico, an alloy of unusual and strong magnetic properties, often used in jet and gas turbine engines.
Cobalt is also used in corrosion and abrasion-resistant steel alloys, especially for very hard applications, as well as in paints and dyes. When cobalt salts are added to glass, porcelain, enamels and pottery, it colors them a brilliant, deep blue. World production is As cobalt is widely dispersed in the environment humans may be exposed to it by breathing air, drinking water and eating food that contains cobalt. Skin contact with soil or water that contains cobalt may also enhance exposure. Cobalt is not often freely available in the environment, but when cobalt particles are not bound to soil or sediment particles the uptake by plants and animals is higher and accumulation in plants and animals may occur.
Cobalt is beneficial for humans because it is a part of vitamin B 12 , which is essential for human health. Cobalt is used to treat anaemia with pregnant women, because it stimulates the production of red blood cells.
The total daily intake of cobalt is variable and may be as much as 1 mg, but almost all will pass through the body unadsorbed, except that in vitamine B However, too high concentrations of cobalt may damage human health. When we breathe in too high concentrations of cobalt through air we experience lung effects, such as asthma and pneumonia.
This mainly occurs with people that work with cobalt. When plants grow on contaminated soils they will accumulate very small particles of cobalt, especially in the parts of the plant we eat, such as fruits and seeds.
Soils near mining and melting facilities may contain very high amounts of cobalt, so that the uptake by humans through eating plants can cause health effects. Health effects that are a result of the uptake of high concentrations of cobalt are: - Vomiting and nausea - Vision problems - Heart problems - Thyroid damage Health effects may also be caused by radiation of radioactive cobalt isotopes.
This can cause sterility, hair loss, vomiting, bleeding, diarrhoea, coma and even death. This radiation is sometimes used with cancer-patients to destroy tumors. These patients also suffer from hair loss, diarrhea and vomiting.
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