Fosforipentakloridi

Fosforipentakloridi, also known as phosphorus pentachloride, is a chemical compound with the formula PCl5. It is a pale yellow solid at room temperature and sublimes readily. PCl5 is a strong chlorinating agent and is often used in organic synthesis. It reacts vigorously with water to produce phosphoric acid and hydrochloric acid. The reaction can be represented as PCl5 + 4H2O -> H3PO4 + 5HCl.

In its solid state, PCl5 exists as an ionic compound, [PCl4]+[PCl6]-. However, in the gas phase and in solution, it primarily exists as discrete PCl5 molecules. The molecule has a trigonal bipyramidal geometry according to VSEPR theory, with the phosphorus atom at the center and five chlorine atoms arranged around it. Two of the chlorine atoms are axial, and three are equatorial.

Industrially, phosphorus pentachloride is produced by the reaction of phosphorus trichloride with chlorine gas: PCl3 + Cl2 -> PCl5. It finds applications in the production of phosphorus oxychloride (POCl3), which is used in the manufacture of plasticizers, flame retardants, and pesticides. It is also used in the synthesis of certain organic compounds, such as alkyl chlorides and acyl chlorides, by replacing oxygen atoms with chlorine atoms or hydroxyl groups with chlorine atoms. Due to its reactive nature, PCl5 must be handled with care in a well-ventilated area, as it is corrosive and produces irritating fumes upon contact with moisture.