NH4SCN, or ammonium thiocyanate, is a chemical compound composed of ammonium ions (NH4+) and thiocyanate ions (SCN-). It appears as a white crystalline solid and is highly soluble in water. This compound is often used in laboratories and various industrial applications, including as a reagent in chemical synthesis and in the production of certain fertilizers. In addition to its practical uses, NH4SCN has interesting properties, such as its ability to lower the freezing point of water when dissolved. This characteristic makes it useful in certain cooling applications. However, it should be handled with care, as it can be toxic in large quantities.