The maximum covalency of a non-metallic group 15 element ' E ' with weakest E-E bond is :
- 5
- 3
- 4
- 6
Answer
(3) 4
Solution
Weakest E–E bond among N, P: N–N (160) < P–P (200 kJ mol-1) because of lone-pair repulsion ⇒ E = N.
N has no d-orbitals, so its covalency stops at 4, as in NH4+.
Answer: (3)