Which of the Following Pairs are Isostructural?

1. a) TiCl₄, SiCl₄
2. b) SO₂⁻³, CrO₂⁻³
3. c) NH₃, NO⁻³
4. d) ClF₃, BCl₃
5. A, B
6. A, C
7. B, C
8. A, D

Answer: (a)

Compounds are said to be iso structural if they share the same hybridization characteristics as well as the same structure.

In scenario (A), the central atom of TiCl₄ is occupied by 4 bonds, and there are no lone pairs present. As a result, it has a tetrahedral shape. In a similar vein, SiCl₄ is a tetrahedral structure.

In scenario (B), the structure of SO₂⁻⁴ is tetrahedral because it contains four lone pairs on the central atom but no other types of bonds. Similarly, CrO₂⁻⁴ also possesses four lone pairs and four covalent bonds on its central atom. The structures of SO₂⁻⁴ and CrO₂⁻⁴, as described by VSEPR, are as follows: