Ammonium sulfate ((NH₄)₂SO₄) is a white, crystalline fertilizer that provides plants with two essential nutrients: nitrogen (21%) and sulfur (24%). It is highly soluble in water and is often used to promote growth in crops like corn and wheat. It also helps lower soil pH, making it beneficial for acidic soils. Besides agriculture, ammonium sulfate is used in industrial applications such as chemical production and water treatment.