Redox Reaction

Redox reactions are reactions in which there's a simultaneous transfer of electrons from one chemical species to another. It is really composed of two different reactions: oxidation (a loss of electrons) and reduction (a gain of electrons). These two things have to happen together in order for a redox reaction to occur. One common example of a redox reaction is rust, as shown on this iron crate near the high school. Rust is the flaky brown substance that forms on iron objects left exposed to the elements too long, especially if the object gets wet. The iron actually turns into rust, which is actually a form of oxidized iron. The chemical reaction of rusting is iron + water + air = rust. When iron is in the presence of moisture, it will lose electrons, becoming a positively charged ion in water (oxidation reaction). Those electrons are then used to reduce the oxygen dissolved in the water (reduction reaction). Those ions react with ions in the water to produce iron hydroxide which will dry in several steps to produce rust.