What is the chemical formula of aluminum foil? - Printable Version +- ask aluminium Forum (https://www.askaluminium.com) +-- Forum: My Category (https://www.askaluminium.com/Forum-My-Category) +--- Forum: aluminium faq (https://www.askaluminium.com/Forum-aluminium-faq) +--- Thread: What is the chemical formula of aluminum foil? (/Thread-What-is-the-chemical-formula-of-aluminum-foil)

What is the chemical formula of aluminum foil? - ZellaHyday - 07-06-2018 The composition of aluminum foil is NOT 100% pure aluminum, as many people believe. You may have noticed that aluminum foil always seems dull on one side, and shiny on the other. This is caused by a naturally-occurring reaction.  When Aluminum comes into contact with oxygen, the two elements undergo a spontaneous reaction:. 4 Al (S) + 3 O 2 (G) => 2 Al 2 O 3 (S) . The aluminum foil reacts with oxygen in the air to form a thin layer of Aluminum Oxide on one side of the foil. Because rolls of aluminum foil are generally rolled tightly, the inner side of the aluminum foil is not exposed to the air as much, and it remains shiny.. In short, the composition of aluminum foil is pure aluminum (Al) AND aluminum oxide (AL 2 O 3 ).. (And don't worry-- the layer of aluminum oxide on aluminum foil is completely harmless. We've been using foil to cover food for years, after all.) RE: What is the chemical formula of aluminum foil? - lolitahe69 - 06-25-2021 Aluminum foil is made by rolling sheets of 98.5 percent pure aluminum metal between steel rollers. Therefore there is no “chemical formula.” There are no Metallurgical additions to create an aluminum alloy either. The Atomic Symbol “Al” and Atomic Number 13 are the proper identifiers.