Question

In case of nitrogen, NCl₃ is possible but not NCl₅ while in case of phosphorus, PCl₃ as well as PCl₅ are possible. It is due to
(a) availability of vacant d orbitals in P but not in N
(b) lower electronegativity of P than N
(c) lower tendency of Hbond formation in P than N
(d) occurrence of P in solid while N in gaseous state at room temperature.

Answer 1

(a) : ₇N = 1s² 2s² 3p³
₁₅P = 1s² 2s² 2p⁶ 3s² 3p³
In phosphorus the 3dorbitals are available.