Sodium alum, also known as sodium aluminum sulfate, is a chemical compound commonly used in various industries. It appears as a white crystalline powder and is often found in baking powder, where it acts as a leavening agent. This means it helps baked goods rise by producing carbon dioxide when mixed with moisture and heat. In addition to its culinary uses, sodium alum is also utilized in water purification processes. It helps to clarify water by causing impurities to clump together, making them easier to remove. This makes it an important component in ensuring clean drinking water for communities around the world.