Practicing Success
Which of the following is not formed on hydrolysis of PCl5? |
POCl3 H3PO4 HCl PCl3 |
PCl3 |
The correct answer is option 4. \(PCl_3\). When phosphorus pentachloride (PCl₅) undergoes hydrolysis, it reacts with water to form phosphoric acid (H₃PO₄), hydrogen chloride (HCl), and intermediates such as phosphorus oxychloride (POCl₃). The complete hydrolysis reaction does not produce phosphorus trichloride (PCl₃). Hydrolysis of PCl₅: 1. Initial Hydrolysis: \(\text{PCl}_5 + \text{H}_2\text{O} \rightarrow \text{POCl}_3 + 2\text{HCl}\) Phosphorus pentachloride reacts with water to form phosphorus oxychloride (POCl₃) and hydrogen chloride (HCl). 2. Further Hydrolysis of POCl₃: \(\text{POCl}_3 + 3\text{H}_2\text{O} \rightarrow \text{H}_3\text{PO}_4 + 3\text{HCl}\) Phosphorus oxychloride further hydrolyzes to form phosphoric acid (H₃PO₄) and more hydrogen chloride (HCl). Overall Hydrolysis: The overall reaction can be written as: \(\text{PCl}_5 + 4\text{H}_2\text{O} \rightarrow \text{H}_3\text{PO}_4 + 5\text{HCl} \) Compounds Formed: H₃PO₄ (Phosphoric Acid): Final product of complete hydrolysis. HCl (Hydrogen Chloride): Produced in both steps of the hydrolysis. Not Formed: PCl₃ (Phosphorus Trichloride): Phosphorus trichloride is not formed during the hydrolysis of PCl₅. Instead, PCl₃ would itself undergo hydrolysis to form H₃PO₃ (phosphorous acid) and HCl. |