Isostructural species are those which have the same shape and hybridisation. Among the given species identify the isostructural pairs.
A. [NF₃ and BF₃ ]

B. [BF₄^- and NH₄⁺ ]

C. [BCl₃ and BrCl₃]

D. [NH₃ and NO₃^-]

Isostructural species are those which have the same shape and hybridization.

NF₃ is pyramidal whereas BF₃ is planar triangular.
BF^–₄ and NH⁺₄ ions both are tetrahedral.
BCl₃ is a triangular planar whereas BrCl₃ is pyramidal.
NH₃ is pyramidal whereas NO₃ is a triangular planar.

Thus, option (ii) is correct.