Question

In case of nitrogen, $NCl_3$ is possible but not $NCl_5$ while in case of phosphorus, $PCl_3$ as well as $PCl_5$ are possible. It is due to

• A. availability of vacant d orbitals in P but not inN
• B. lower electronegativity of P than N
• C. lower tendency of H-bond formation in P thanN
• D. occurrence ofP in solid while N in gaseous state at room temperature.

Answer 1

Answer: (A)

availability of vacant d orbitals in P but not inN

Answer 2

$_{7}N= 1s^{2} \,2s^{2} \,2p^{3}; \quad_{15}P = 1s^{2} \,2s^{2} \,2p^{6} \,3s^{2} \, 3p^{3}$
In phosphorous the 3J-orbitals are available. Hence phosphorus can form pentahalides also but nitrogen cannot form pentahalide due to absence of d-orbitals.