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Superconductivity is a state of matter that chemical element compounds and alloys assume on being cooled to temperatures οθ to absolute zero. Hence, a superconductor is a solid material that abruptly loses all resistance to the flow of electric current when cooled below a characteristic temperature. This temperature differs for different materials but generally is within the absolute zero (-273° C). Superconductors have thermal, electric and magnetic properties that differ from their properties at higher temperatures and from properties of nonsuperconductive materials.

Now hundreds of materials are known to become superconductors at low temperature. Approximately 26 of the chemical elements are superconductors. Among these are commonly known metals such aluminium, tin, lead and mercury and several less common ones.

Most of the known superconductors are alloys or compounds.

It is possible for a compound to be superconducting even if the chemical elements constituting it are not.