Question

Which of the following reactions proves the chlorinating property of phosphorus pentachloride?

• A. \( \text{PCl}_5 + \text{H}_2\text{O} \rightarrow \text{POCl}_3 + 2\text{HCl} \)
• B. \( \text{P}_4 + 10\text{Cl}_2 \rightarrow 4 \text{PCl}_5 \)
• C. \( \text{PCl}_5 \rightarrow \text{POCl}_3 + \text{Cl}_2 \)
• D. \( 2 \text{PCl}_5 + \text{Sn} \rightarrow \text{SnCl}_4 + 2 \text{PCl}_3 \)

Hint:

Phosphorus pentachloride is an excellent chlorinating agent, and its reaction with tin is a key example.

Answer 1

The Correct Option is D

Step 1: Understanding the chlorinating property of \text{PCl_5.}
Phosphorus pentachloride (\text{PCl}_5) is a chlorinating agent that reacts with various substances to replace or add chlorine atoms. The reaction with tin (Sn) is a classic example of its chlorinating property.

Step 2: Analyzing the options.
(A) \( \text{PCl}_5 + \text{H}_2\text{O} \): This reaction shows the hydrolysis of \text{PCl}_5, not its chlorinating property.
(B) \( \text{P}_4 + 10\text{Cl}_2 \): This is the formation of \text{PCl}_5 from phosphorus and chlorine, not proof of its chlorinating property.
(C) \( \text{PCl}_5 \rightarrow \text{POCl}_3 + \text{Cl}_2 \): This shows decomposition of \text{PCl}_5, but not its chlorinating property.
(D) \( 2 \text{PCl}_5 + \text{Sn} \): Correct — This reaction demonstrates the chlorinating property of \text{PCl}_5, where it chlorinates tin to form SnCl₄ and PCl₃.

Step 3: Conclusion.
The correct answer is (D) as it directly demonstrates the chlorinating ability of phosphorus pentachloride.