In which of the following pairs of molecules/ions, the central atoms have sp ^2 hybridisation?

Step-by-step solution

Key Idea For sp ^2 hybridisation, there must be 3 -bonds or 2 -bonds along with a lone pair of electrons. (i) NO ₂⁻ 2 +1 lp =3 , ie, sp ^2 hybridisation (ii) NH ₃ 3 +1 lp =4 , ie, sp ^3 hybridisation (iii) BF ₃ 3 +0 lp =3 , ie, sp ^2 hybridisation (iv) NH ₂⁻ 2 +2 lp =4 , ie, sp ^3 hybridisation (v) H ₂ O 2 +2 lp =4 , ie, sp ^3 hybridisation Thus, among the given pairs, only BF ₃ and NO ₂⁻ have sp ^2 hybridisation.