Alum, also known as aluminum sulfate, is a chemical compound with the formula Al2(SO4)3. It is widely recognized for its versatile applications in various industries. Alum is commonly used as a coagulant in water treatment processes to clarify turbid water by removing suspended particles. Additionally, it has a history of use in pickling to crisp fruits and vegetables and as an ingredient in baking powder for leavening. Alum also finds use in cosmetics, textiles, and as a mordant in dyeing processes. Its astringent properties have made it a traditional remedy for various skin conditions. Overall, alum's ability to form solid precipitates and its diverse range of applications make it a valuable chemical compound in both industrial and household settings.