Phosphorus Pentachloride: Dry Chlorine Passed over Cooled Phosphorus Trichloride (Thorpe 1912)

Liquid phosphorus trichloride takes up more chlorine and turns into solid phosphorus pentachloride. Keep the liquid cold and pass dry chlorine over it until everything has gone dry. Result: white, lustrous crystals of PCl5, used to turn organic acids into their chlorides. Source: Thorpe, Dictionary of Applied Chemistry, vol. 4 (1912), Phosphorus. Not given: amounts, how the chlorine is dried. Danger: chlorine is a deadly gas; the product fumes in moist air. Picture drawn by Youblob.