Draw the structures of the following: (a) XeF₄ (b) BrF₅

(a) XeF₄

Xe has 8 valence electrons. Four of these are used in bonding with four F atoms. This leaves 4 electrons which form two lone pairs. The structure is based on an octahedral geometry (6 electron pairs around the central Xe atom), but because of the two lone pairs, the molecular geometry is square planar.

[Diagram of square planar XeF₄ would be inserted here showing Xe in the center with four F atoms at the corners of a square and two lone pairs above and below the plane. Note: I cannot create visual diagrams in this text-based response.]

(b) BrF₅

Br has 7 valence electrons. Five of these are used in bonding with five F atoms. This leaves 2 electrons which form one lone pair. The structure is based on an octahedral geometry (6 electron pairs around the central Br atom). Because of the one lone pair, the molecular geometry is square pyramidal.

[Diagram of square pyramidal BrF₅ would be inserted here showing Br in the center with five F atoms forming a square pyramidal shape, and one lone pair on the Br atom. Note: I cannot create visual diagrams in this text-based response.]