The product formed in the reaction of SOCl2 with white phosphorous is
P4 + SOCl2 → PCl3 + SO2 + S2Cl2
The reaction between thionyl chloride (SOCl2) and white phosphorus (P4) is an important reaction in inorganic chemistry. White phosphorus is a highly reactive form of phosphorus that exists as P4 molecules. When it reacts with SOCl2, the primary product formed is phosphorus trichloride (PCl3). The reaction can be represented by the following balanced chemical equation:
In this reaction, SOCl2 acts as a chlorinating agent, converting white phosphorus (P4) into PCl3. The other products are sulfur dioxide (SO2) and sulfur monochloride (S2Cl2). It is important to note that PCl3 is the main phosphorus-containing product, making it the correct answer among the options provided.
Reactivity of White Phosphorus: White phosphorus is highly reactive due to its strained P4 tetrahedral structure, which has bond angles of 60°, leading to high instability and reactivity, especially with halogens and halogenating agents like SOCl2.
Role of SOCl2: Thionyl chloride is commonly used as a chlorinating agent in organic and inorganic chemistry. It is particularly effective for converting hydroxyl groups to chlorides, but it also reacts with elements like phosphorus to form chlorides.
Key Formula: The stoichiometry of the reaction is crucial. For every mole of P4, 8 moles of SOCl2 are required to produce 4 moles of PCl3, along with other by-products.
The hottest region of Bunsen flame shown in the figure below is :
