question_answer

Which one of the following pairs is  isostructural (i.e., having the same shape and hybridization)? [AIPMT (S) 2012]

A)  \[[BC{{l}_{3}}\,\text{and}\,BrC{{l}_{3}}]\]

B)       \[[N{{H}_{3}}\,\text{and}\,NO_{3}^{-}]\]

C)  \[[N{{F}_{3}}\,\text{and}\,B{{F}_{3}}]\]

D)       \[[BF_{4}^{-}\,\text{and}\,NH_{4}^{+}]\]

Correct Answer: D

Solution :

If number of bond pairs and lone pairs are same for the given pairs, they are

is structural.

[a]\[BC{{l}_{3}}\]and\[BrC{{l}_{3}}\]

[b]\[N{{H}_{3}}\,\text{and}\,NO_{3}^{-}\]

[c]\[N{{F}_{3}}\,\text{and}\,BF_{3}^{{}}\]

[d]\[BF_{4}^{-}\,\text{and}\,NH_{4}^{+}\]

Thus, \[BF_{4}^{-}\,\text{and}\,NH_{4}^{+}\]are isostructural.