Quicklime, also known as calcium oxide, is a white, caustic solid that is produced by heating limestone in a process called calcination. This process removes carbon dioxide from the limestone, resulting in quicklime. It is commonly used in various industries, including construction, where it serves as a key ingredient in making cement and mortar. When quicklime is mixed with water, it undergoes an exothermic reaction to form slaked lime or calcium hydroxide. This reaction generates heat and produces a milky solution that is used in applications such as water treatment, soil stabilization, and as a pH regulator in various chemical processes.