A Single Replacement Reaction is a type of chemical reaction where one element replaces another element in a compound. This occurs when a more reactive element displaces a less reactive one. For example, in the reaction between zinc and copper(II) sulfate, zinc replaces copper, forming zinc sulfate and releasing copper. These reactions can be represented by the general formula: A + BC → AC + B, where A is the single element, and BC is the compound. Single replacement reactions are commonly seen in metallurgy and electrochemistry, showcasing the reactivity series of metals.