Aluminium is a pure chemical substance that cannot be broken down further. It has an atomic number of 13, which implies that it has 13 protons in its nucleus. It also has 13 electrons. Aluminium belongs to the group 13 in the periodic table, which also includes boron, gallium, indium and thallium. Aluminium’s atomic weight is 26.98 atomic mass units (amu). Aluminium exists in nature in various compounds and due to its high affinity to bind with oxygen, it is found only in combined forms such as oxides or silicates.

Aluminium is a good conductor of heat and electricity. It is light, malleable, ductile and resistant to corrosion. It exhibits high reflectivity and is non-magnetic. Aluminium has a melting point of 660°C and a boiling point of 2,327-2,450°C. The density is 2.708 grams per cubic centimetre.

Aluminium is resistant to rust. The metal combines slowly with oxygen to form aluminium oxide, which forms a thin, white coating on the metal. This coating prevents aluminium from reacting further with oxygen and protects it from rusting.

Aluminium is an amphoteric element which reacts with many hot acids and alkalis. The metal reacts quickly with hot water and in powdered form catches fire quickly when exposed to a flame.

Aluminium is used for making small containers and cans with the additional advantage that aluminium cans are easily recyclable. It is estimated that the turnaround between the time a can is tossed into a recycling bin, re-smelted, fabricated and put back on a store shelf is only 60 days. Due to its property of high reflectivity, aluminium surfaces make excellent mirrors.

The metal is used widely for windows, doors and skylights because it has low rates of expansion and contraction and is highly resistant and rigid. Aluminium building products help keep homes cool in summer and warm in winter.

Aluminium funds extensive applications in transportation due to its lightness, strength and formability. Usage of aluminium in trucks, cars and trains reduces energy consumption by these vehicles and arrests greenhouse emissions. Aluminium is used as crash management systems and in frames and wheels to enhance safety of vehicles. In the aviation sector, aluminium is used for internal fittings such as seats to save weight, fuel and increase the aircraft's payload.

The packaging industry uses aluminium extensively due to the lightness of the metal, which helps to reduce transport costs. The metal can be rolled into ultra-thin foils that are strong and protect from ultra-violet light, odours and bacteria. A number of aluminium packaging applications are used in food, medicine and cosmetics.

Due to its properties, aluminium has been able to replace steel in various industries over the past several years. In the construction and transportation industries in particular, aluminum has been preferred due to its lighter weight, robustness and lesser time that is required for fabrication. In addition to this, the fact that aluminium does not rust but steel does adds to the allure of the former.