Aluminium - Overview, Properties & Uses, Sources, FAQs

Aluminium is soft, silvery-white, ductile, and nonmagnetic element. In the Earth's crust, it is the third most plentiful element. Aluminium comes in a variety of colours, ranging from silvery to drab grey, depending on the surface reference. Aluminium, a member of the Boron family, is a well-known "group 13" element. Aluminium Electronic Configuration is 1s² 2s² 2p⁶ 3s² 3p¹. Aluminium atomic number is 13. Aluminium symbol is Al.

As it has an extra electron orbit than Boron, the sum of the first three ionisation enthalpies of Aluminium is lower than Boron's, allowing it to form Al³⁺ ions. It is a strongly electropositive element that, like Aluminium Oxide, usually produces +3 oxidation states (Al₂O₃). Mass number of aluminium is 26.98u

Physical Properties Of Aluminium

The physical properties of an element deals with properties such as color, melting point, boiling point, density, conductivity, solubility among others.

This element has a high reactivity. Steel's rigidity and density of aluminum are around one-third of that of this material.

Aluminium is a corrosion-resistant metal and atomic mass of aluminium is 27amu.

Boiling point of aluminum is 2,470 degree Celsius

It has the ability to conduct electricity in a superconducting state.

There are numerous unidentified isotopes with atomic mass of aluminium or mass of Al ranging from twenty-one to forty-one.

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Chemical Properties Of Aluminium

Follwing are the chemical properties of Aluminium:

1. Aluminium with HCl reaction

At room temperature, aluminium get reacts with dilute hydrochloric acid. Aluminum chloride and colourless hydrogen gas are produced when the metal aluminium dissolves in hydrochloric acid. The chemical reaction between aluminium and hydrochloric acid is irreversible.

2Al + 6HCl → 2AlCl₃ + 3H₂↑

2. Aluminum Reaction with Sodium hydroxide

The action of sodium hydroxide on elemental aluminium, which is an amphoteric metal, also produces sodium aluminate. Once established, the reaction is highly exothermic and is accompanied by the rapid development of hydrogen gas.

2NaOH + 2H₂O → 2NaAlO₂ + 3H.

3. Aluminum Reaction with water

Aluminum metal forms a thin film of aluminium oxide, a few millimetres thick, that prevents it from interacting with water. According to the equation, aluminium reacts with water to produce hydrogen gas.

2Al + 3H₂O → 3H₂ + Al₂O₃

Uses Of Aluminium And Aluminium Foil

As castings, it is employed in the transportation of railways, trucks, and vehicles.

It's a component of packaging.

Al (II) compounds are formed when Al metal reacts with oxidants.

The presence of aluminium can be determined in qualitative analysis using aluminon.

Aluminum foil, commonly known as tin foil, is a slick, paper-thin sheet of aluminium metal. It is made by rolling atomic mass of aluminiumive slabs of aluminium until they are less than 0.2 mm thick.

Insulation, packing, and shipping are just a few of the applications for aluminium foil in the industrial world. It's also commonly available at all grocery stores for usage in the home. Aluminum foil is used in the home to store food, wrap goods, and cover baking surfaces such as meat to avoid moisture loss when cooking.

Aluminum foil is also used to wrap and protect more delicate foods, such as vegetables, while they are being grilled.

Aluminium Ore Extraction

A silky, silvery-white metal that resists corrosion. It is the most plentiful metal in the earth's crust, accounting for 8% of it, and the third most abundant element after oxygen and silicon. Until now, bauxite ore (Al₂O₃.xH₂O), a combination of hydrated aluminium oxide, has been the primary source of aluminium.

Cryolite (Na₃AlF₆) and alunite can also be used to recover aluminium. Garnet, topaz, and chrysoberyl are some of the gemstones that contain it. Al is the chemical aluminum symbol for this metal. Aluminium is a chemical element that belongs to the boron group and has the symbol Al. It is most commonly used non-ferrous metal.

Ores of Aluminium

Aluminum is a highly reactive metal that belongs to the periodic table's IIIA group. Aluminium is present in its ores in the form of its oxide in nature. The most important aluminium ores are

Bauxite – Al₂O₃.2H₂O

Corundum – Al₂O₃

Cryolite – Na₃AlF₆

Meltallurgy of Aluminium

Concentration of ore

Impurities in bauxite ore include ferric oxide and silica. It is concentrated first by gravity separation of ferric oxide impurities, followed by a magnetic separation process. After that, the ore is concentrated using a chemical process.

Aluminium ore is referred to as bauxite. Bauxite is refined to produce aluminium oxide, a white powder from which aluminium may be extracted.

Ferric oxide and silica are two impurities found in bauxite ore. It is concentrated first by separating ferric oxide impurities by gravity, then by a magnetic separation method. The ore is then concentrated by a chemical process.

Bauxite is the name for aluminium ore. Bauxite is processed to generate aluminium oxide, a white powder that may be used to extract aluminium.

Metallurgy of Aluminium

The primary source of aluminium is bauxite ore. Ore dressing entails crushing and pulverising the ore.

Bayer’s Process

Aluminium ore is processed with concentrated sodium hydroxide in this procedure. It produces soluble sodium aluminate, which is filtered out. When the filtrate is heated with water, it produces aluminium hydroxide, which when heated further produces alumina.

Hall-Heroult Process

In the extraction of aluminium, the Hall-Heroult technique is commonly utilized. Pure Al₂O₃ is combined with CaF₂ or Na₃AlF₆ in the Hall-Heroults process. As a result, the melting point of aluminum of the combination is lowered, and its ability to conduct electricity is increased. The vessel is made of steel with a carbon and graphite rod liner.

The cathode is the carbon lining, and the anode is graphite.When electricity is transmitted through a carbon electrode electrolytic cell, oxygen is produced at the anode. Carbon monoxide and carbon dioxide are created when the oxygen produced reacts with the carbon in the anode. In this process of aluminium manufacturing, approximately 0.5 kilogramme of carbon anode is burned for every 1 kg of Al produced.

2Al₂O₃ + 3C → 4Al + 3CO₂

The electrolytic reactions:

At cathode:

Al³⁺ + 3e^– → Al (l)

At anode:

C (s) + O^2- → CO (g) + 2e^–

C (s) + 2O²- → CO₂ (g) + 4e^–

Positively charged aluminium ions gain electrons from the cathode and create molten aluminium during the electrolysis process.

Oxide ions lose their anode electrons and produce oxygen molecules.

Aluminium is too large to be extracted from its ore by carbon reduction in the electrochemical sequence, which is also known as the reactivity series. Temperatures necessary are far too high to be cost-effective.