Glossary Allotropes Some elements exist in several different structural forms, called allotropes. Discovery date Discovered by Hans Oersted Origin of the name The name is derived from the Latin name for alum, 'alumen' meaning bitter salt. Glossary Group A vertical column in the periodic table. Fact box. Group 13 Melting point 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. Aircraft fuselages and aluminium foil are just two of the many and varied uses of this element. Aluminium is a silvery-white, lightweight metal.
It is soft and malleable. Aluminium is used in a huge variety of products including cans, foils, kitchen utensils, window frames, beer kegs and aeroplane parts. This is because of its particular properties. It has low density, is non-toxic, has a high thermal conductivity, has excellent corrosion resistance and can be easily cast, machined and formed.
It is also non-magnetic and non-sparking. It is the second most malleable metal and the sixth most ductile. It is often used as an alloy because aluminium itself is not particularly strong. Alloys with copper, manganese, magnesium and silicon are lightweight but strong. They are very important in the construction of aeroplanes and other forms of transport.
Aluminium is a good electrical conductor and is often used in electrical transmission lines. It is cheaper than copper and weight for weight is almost twice as good a conductor. When evaporated in a vacuum, aluminium forms a highly reflective coating for both light and heat. It does not deteriorate, like a silver coating would. These aluminium coatings have many uses, including telescope mirrors, decorative paper, packages and toys. Biological role. Aluminium has no known biological role.
Our bodies absorb only a small amount of the aluminium we take in with our food. Foods with above average amounts of aluminium are tea, processed cheese, lentils and sponge cakes where it comes from the raising agent.
Cooking in aluminium pans does not greatly increase the amount in our diet, except when cooking acidic foods such as rhubarb. Some indigestion tablets are pure aluminium hydroxide. Natural abundance. It is usually found in minerals such as bauxite and cryolite.
These minerals are aluminium silicates. In this process aluminium oxide is dissolved in molten cryolite and then electrolytically reduced to pure aluminium. Making aluminium is very energy intensive. However, once it has been made it does not readily corrode and can be easily recycled. Help text not available for this section currently.
Elements and Periodic Table History. How it was produced remains a mystery. By the end of the s, aluminium oxide was known to contain a metal, but it defeated all attempts to extract it. The first person to produce it was Hans Christian Oersted at Copenhagen, Denmark, in , and he did it by heating aluminium chloride with potassium.
Even so, his sample was impure. Atomic data. Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom. Oxidation states and isotopes. Glossary Data for this section been provided by the British Geological Survey. Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk. Recycling rate The percentage of a commodity which is recycled.
Substitutability The availability of suitable substitutes for a given commodity. Reserve distribution The percentage of the world reserves located in the country with the largest reserves. Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators. Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators.
Supply risk. Relative supply risk 4. Young's modulus A measure of the stiffness of a substance. Shear modulus A measure of how difficult it is to deform a material.
Bulk modulus A measure of how difficult it is to compress a substance. Vapour pressure A measure of the propensity of a substance to evaporate.
Pressure and temperature data — advanced. Listen to Aluminium Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry. This week the chemical cause of transatlantic linguistic friction. Is it an um or an ium at the end? It turns out us Brits might have egg on our faces as well as a liberal smattering of what we call aluminium.
It's a common refrain of the flying-phobic, but maybe they would find comfort in knowing that the box is actually made of aluminium - more than kg of it, if they're sitting in a jumbo jet. While lamenting one's presence in an 'aluminium box' doesn't have quite the same ring, there are several good reasons to appreciate this choice of material. Pure aluminium is soft. However, alloying it with elements such as such as copper, magnesium, and zinc, dramatically boosts its strength while leaving it lightweight, obviously an asset when fighting against gravity.
The resulting alloys, sometimes more malleable than aluminium itself, can be moulded into a variety of shapes, including the aerodynamic arc of a plane's wings, or its tubular fuselage. And whereas iron rusts away when exposed to the elements, aluminium forms a microscopically thin oxide layer, protecting its surface from further corrosion.
With this hefty CV, it's not surprising to find aluminium in many other vehicles, including ships, cars, trucks, trains and bicycles. Happily for the transportation industry, nature has blessed us with vast quantities of aluminium. The most abundant metal in the earth's crust, it's literally everywhere. Yet aluminium remained undiscovered until , as it's bound up with oxygen and silicon into hundreds of different minerals, never appearing naturally in its metallic form.
Sir Humphrey Davy, the Cornish chemist who discovered the metal, called it 'aluminum', after one of its source compounds, alum. In a further twist to the nomenclature story, the American Chemical Society resurrected the original spelling in , and so ironically it is the Americans and not the British that pronounce the element's name as Davy intended. He reportedly said of his prize, 'It forms a lump of metal that resembles tin in colour and sheen" - not an overly flattering description, but possibly an explanation for airline passengers' present confusion.
The difficulty of ripping aluminium from its oxides - for all early processes yielded only kilogram quantities at best - ensured its temporary status as a precious metal, more valuable even than gold. In fact, an aluminium bar held pride of place alongside the Crown Jewels at the Paris Exhibition, while Napoleon is said to have reserved aluminium tableware for only his most honoured guests. It wasn't until that Charles Martin Hall, an uncommonly dogged, amateur scientist of 22, developed the first economic means for extracting aluminium.
Industrial production world-wide of new metal is around 20 million tons per year, and a similar amount is recycled. Known reserves of ores are 6 billion tones. Aluminum is one of the most widely used metals and also one of the most frequently found compounds in the earth's crust. Due to these facts, aluminum is commonly known as an innocent compound. But still, when one is exposed to high concentrations, it can cause health problems.
The water-soluble form of aluminum causes the harmful effects, these particles are called ions. They are usually found in a solution of aluminum in combination with other ions, for instance as aluminum chlorine. The uptake of aluminum can take place through food, through breathing and by skin contact. Long lasting uptakes of significant concentrations of aluminum can lead to serious health effects, such as: - Damage to the central nervous system - Dementia - Loss of memory - Listlessness - Severe trembling Aluminum is a risk in certain working environments, such as mines, where it can be found in water.
People that work in factories where aluminum is applied during production processes may endure lung problems when they breathe in aluminum dust. Aluminum can cause problems for kidney patients when it enters the body during kidney dialyses. Inhalation of finely divided aluminum and aluminum oxide powder has been reported as a cause of pulmonary fibrosis and lung damage.
The effects of aluminum have drawn our attention, mainly due to the acidifying problems. Aluminum may accumulate in plants and cause health problems for animals that consume these plants. The concentrations of aluminum appear to be highest in acidified lakes. In these lakes the number of fish and amphibians is declining due to reactions of aluminum ions with proteins in the gills of fish and the embryo's of frogs. High aluminum concentrations do not only cause effects upon fish, but also upon birds and other animals that consume contaminated fish and insects and upon animals that breathe in aluminum through air.
The consequences for birds that consume contaminated fish are eggshell thinning and chicks with low birth-weights. The consequences for animals that breathe in aluminum through air may be lung problems, weight loss and a decline in activity. Another negative environmental effect of aluminum is that its ions can react with phosphates, which causes phosphates to be less available to water organisms.
High concentrations of aluminum may not only be found in acidified lakes and air, but also in the groundwater of acidified soils. There are strong indications that aluminum can damage the roots of trees when it is located in groundwater. We cab tell you more about the behaviour of aluminum in water.
Back to periodic chart. Malleability High malleability. Aluminum is very capable of being shaped or bent. Thermal Expansion Aluminum has a thermal expansion coefficient of This is between zinc—which expands more—and steel, which expands half the range of aluminum. Conductivity Good electrical and thermal conductor. Corrosion Aluminum is corrosive resistant due to a self-protecting oxide layer.
Density Aluminum has a low density, measured by gravity in comparison to water, of 2. These change once aluminum is alloyed. Takeaways for Physical Properties of Aluminum Physical properties of aluminum help make sense of its applications. The Chemical Properties of Aluminum Occurrence Aluminum occurs as a compound, principally found in bauxite ore.
Oxidation Aluminum combines with oxygen to form aluminum oxide when exposed to moist air. Pyrophorus When aluminum is in a powdered form it will catch fire easily if exposed to flame. Ability to form alloys Hundreds of aluminum alloy compositions exist. Alloyed elements include: iron, copper, manganese, silicon, magnesium, and zinc. Reactivity with water Aluminum reacts quickly with hot water.
Reactivity with alkalis Reactive with sodium hydroxide. Reactivity with acid Aluminum reacts with hot acids. Takeaways for Chemical Properties of Aluminum In some ways, the chemical properties of aluminum are unusual compared to other metals.
Mechanical Properties Mechanical properties note a materials relationship between stress and strain and measure the degree of elasticity in response to an applied load. Compare this to copper at ksi or wood at ksi.
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