JEE Main · 2025 · 04 Apr 2025 · Shift 2 · Coordination Compounds

In bromine pentafluoride the central bromine is $s{p}^3{d}^2$ hybridised with five bonding pairs and one lone pair, so it bears a single lone pair, which fixes the defined quantity at one. One mole of silver chloride is therefore precipitated by excess silver nitrate, meaning just one chloride lies outside the coordination sphere, and the $s{p}^3{d}^2$ complex is the octahedral $[\mathrm{M}(\mathrm{N}{\mathrm{H}}_3{)}_3\mathrm{C}{\mathrm{l}}_3]\mathrm{Cl}$. An octahedral complex of the type $\mathrm{M}{\mathrm{a}}_3{\mathrm{b}}_3$ occurs as a facial isomer, with the three like ligands on one triangular face, and a meridional isomer, with them spread along a meridian. The number of geometrical isomers exhibited is two.