Aluminum
Definition and meaning of Aluminum in chemistry.
Aluminum is a silvery-white, lightweight metal with atomic number 13 and the third most abundant element in Earth's crust. It is highly valued for its excellent electrical and thermal conductivity, strength-to-weight ratio, and natural resistance to corrosion.
In more detail
Aluminum rapidly forms a protective oxide layer when exposed to air, which prevents further corrosion of the underlying metal, a property that distinguishes it from iron and many other reactive metals. Because of this combination of low density and corrosion resistance, aluminum is extensively used in aircraft, automobiles, and architectural applications. The element is also an excellent conductor of both electricity and heat, making it essential for power transmission lines and electronic components. Aluminum is extracted primarily from bauxite ore through industrial processes including the Bayer process and electrolysis.
Key facts
| Atomic Number | 13 |
|---|---|
| Chemical Formula | Al |
| Density | 2.70 g/cm³ at room temperature |
| Field | Inorganic Chemistry |
Aluminum foil is commonly used in cooking and food storage because of its flexibility, excellent heat distribution, and the protective oxide coating that forms naturally on its surface, preventing the reactive metal from directly contacting food.
Frequently asked questions
Why doesn't aluminum rust like iron?
Aluminum forms a thin, dense oxide coating that forms instantly when exposed to oxygen, creating a protective barrier that prevents further oxidation. Iron oxide (rust), by contrast, is porous and permeable, allowing continued corrosion of the underlying metal.
What is bauxite and where does it come from?
Bauxite is the primary ore from which commercial aluminum is extracted. It is an aluminum oxide mineral found primarily in tropical and subtropical regions, with major deposits in Australia, Guinea, and Brazil.