Calcium oxide reacts with water to produce slaked lime. It is an example of

The reaction between calcium oxide (quicklime) and water to produce calcium hydroxide (slaked lime) is a classic example of a combination reaction. In this process, two distinct reactants—solid calcium oxide and liquid water—combine to form a single product, calcium hydroxide. The chemical equation is represented as CaO + H2O → Ca(OH)2. This specific reaction is highly exothermic, meaning it releases a significant amount of heat during the formation of the product. While the process is also referred to as the 'slaking of lime' or hydration, it fits the fundamental definition of a combination reaction because multiple substances merge into one. It is not a decomposition reaction, as that would involve a single reactant breaking down, nor is it primarily classified as an oxidation or addition reaction in this context.