Phosphorus Pentachloride (PCl₅) is a chemical compound made up of one phosphorus atom and five chlorine atoms. It is a yellowish solid at room temperature and is known for its ability to act as a chlorinating agent in various chemical reactions. PCl₅ is often used in organic synthesis and can convert alcohols into alkyl chlorides. When Phosphorus Pentachloride is heated, it can decompose into Phosphorus Trichloride (PCl₃) and chlorine gas (Cl₂). This compound is also hygroscopic, meaning it can absorb moisture from the air, which can affect its stability and reactivity. Proper handling and storage are essential to ensure safety when working with PCl₅.