The valency of phosphorus in PCl₅ is: MCQ with Answer and Explanation

The valency of phosphorus in PCl₅ is:
A. 5
B. 3
C. 1
D. 6
Answer: Option A
Solution (By JKSSB Mock Tests)
In PCl₅, phosphorus forms five covalent bonds with five chlorine atoms. Phosphorus has 5 valence electrons (3s²3p³), and by using d-orbitals, it can expand its octet to accommodate 5 bonds. Thus its covalency is 5. In PCl₃, it is 3. Valency is the number of bonds formed. The oxidation state of P in PCl₅ is +5.

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