Pá de Cal, also known as quicklime, is a chemical compound made from calcium oxide. It is produced by heating limestone, which is primarily composed of calcium carbonate, in a process called calcination. When water is added to quicklime, it undergoes a reaction to form slaked lime, or calcium hydroxide, which is used in various applications, including construction and agriculture. In construction, Pá de Cal is often used in mortars and plasters due to its ability to harden and bind materials together. It also plays a role in soil stabilization and can help improve the pH of acidic soils in agriculture. Its versatility makes it an important material in many industries, including construction and agriculture.