Here's why:

* Central atom: Bromine (Br) is the central atom.

* Valence electrons: Bromine has 7 valence electrons, and each fluorine (F) atom has 7 valence electrons.

* Bonding: Bromine forms 5 single bonds with the five fluorine atoms.

* Lone pairs: Bromine has one lone pair of electrons.

* VSEPR theory: The five bonding pairs and one lone pair around the bromine atom result in a total of six electron groups. According to the VSEPR theory, the arrangement of six electron groups produces a square pyramidal geometry.

Note: While the electron geometry is square pyramidal, the molecular geometry of BrF₅ is square planar because the lone pair is not included in the molecular shape.