Answer to Question #185326 in Inorganic Chemistry for Luke Zammit

Question

When Br2 and I2 react with phosphorous, only PBr3­ and PI3 are produced. Give a reason for this.

Answer 1

Red phosphorus is an active reactant in the conversion of alcohols to alkyl halides, using either bromine (Br2) or iodine (I2) as the reagent. Phosphorus trihalide is a key intermediate. At the end of the reaction, phosphoric acid is recovered.

Red phosphorus is not a catalyst, because it is actively involved as a reactant in the reaction