Iron oxide Iron oxide (rust) on a bolt. (more) How Does Metal Rust? Ask the Chatbot a Question More Actions Share Share Share to social media Facebook X URL https://www.britannica.com/science/How-Does-Metal-Rust Feedback Corrections? Updates? Omissions? Let us know if you have suggestions to improve this article (requires login). Feedback Type Select a type (Required) Factual Correction Spelling/Grammar Correction Link Correction Additional Information Other Your Feedback Submit Feedback Thank you for your feedback Our editors will review what you’ve submitted and determine whether to revise the article.

　　External Websites Ask the Chatbot a Question Written and fact-checked by The Editors of Encyclopaedia Britannica Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors. The Editors of Encyclopaedia Britannica Last Updated: Apr 8, 2025 • Article History Table of Contents Table of Contents Ask the Chatbot Rust is the result of a chemical reaction between metal, typically iron, and oxygen in the presence of moisture. This process, known as oxidation, transforms the metal into a new compound, iron oxide, which we commonly recognize as rust. The presence of water and oxygen is crucial for rust to form, and this is why metals left exposed to the elements, especially in humid or wet environments, are more prone to rusting. The rusting process begins when iron reacts with water and oxygen. Initially, the iron dissolves in the acidic solution created by moisture and carbon dioxide in the air, ...(100 of 306 words)

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