Answer:
SeCl₆ < SeF₂ < SeO₂
Explanation:
To determine the order of the bond angle of the compound, we need to determine the hybridization of each compound given.
For:
SeO₂, The hybridization is sp² because the Se is doubly bonded to O at both sides and Se contains a lone pair of electrons.
SeCl₆, Se is attached to six different Cl atoms via a single bond in a hexagonal shape. Thus, SeCl₆ hybridization is sp³d²
SeF₂, Here, Se is singly bonded to F atoms on both sides and Se contains a lone pair of electrons. The hybridization is sp³
Therefore, the bond angle in sp² = 120°, sp³ = 109.8°, sp³d² = 90°
Hence, the order is: SeCl₆ < SeF₂ < SeO₂