Draw the Lewis structure of bromine pentafluoride, BrF5.

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Draw the Lewis structure of bromine pentafluoride, BrF5. Do not include brackets or formal charges. If the molecule exhibits resonance, draw only one (1) of the resonance forms. Hartree-Fock method can be used to help with the drawing. Edit drawing. What is the electron-pair geometry of bromine pentafluoride? What is the shape (molecular geometry) of bromine pentafluoride? What is the hybridization of the central atom? sp3d2

The Correct Answer and Explanation is:

Lewis Structure of BrF5:

  1. Determine the total number of valence electrons:
    • Bromine (Br) is in Group 17, so it has 7 valence electrons.
    • Fluorine (F) is also in Group 17, and each fluorine atom has 7 valence electrons. Since there are 5 fluorine atoms, this contributes 5×7=355 \times 7 = 355×7=35 valence electrons.
    • Total valence electrons = 7(Br)+35(F)=427 (Br) + 35 (F) = 427(Br)+35(F)=42 valence electrons.
  2. Arrange atoms:
    Bromine is the central atom, as it is less electronegative than fluorine.
  3. Connect the atoms with single bonds:
    Place a single bond between Br and each of the five F atoms. Each single bond represents 2 electrons. For 5 bonds, we use 5×2=105 \times 2 = 105×2=10 electrons.
  4. Distribute the remaining electrons:
    After forming the bonds, we have 42−10=3242 – 10 = 3242−10=32 electrons left. These will be placed as lone pairs on the fluorine atoms first. Each fluorine atom needs 3 more pairs (6 electrons) to complete its octet. This uses up 5×6=305 \times 6 = 305×6=30 electrons, leaving 2 electrons.
  5. Place the remaining electrons on the central atom (Br):
    Bromine, being in Period 4, can accommodate more than 8 electrons. The 2 remaining electrons are placed as a lone pair on the bromine atom.
  6. Final Lewis Structure:
    Bromine is surrounded by five single bonds to fluorine atoms, with each fluorine having 3 lone pairs. Bromine also has one lone pair.

Electron-pair Geometry and Molecular Geometry:

  • Electron-pair Geometry: Bromine pentafluoride (BrF5) has 6 regions of electron density (5 bonding pairs and 1 lone pair). According to the VSEPR (Valence Shell Electron Pair Repulsion) theory, the electron-pair geometry around the central atom is octahedral.
  • Molecular Geometry: The lone pair on bromine occupies one of the positions in the octahedral geometry, leaving the fluorine atoms in a square pyramidal arrangement. Therefore, the molecular geometry of BrF5 is square pyramidal.

Hybridization of the Central Atom:

  • The central bromine atom is involved in 5 bonds and 1 lone pair, which requires 6 orbitals. The hybridization of the central atom is sp3d2, which corresponds to an octahedral geometry.

Summary:

  • Electron-pair Geometry: Octahedral
  • Molecular Geometry: Square pyramidal
  • Hybridization: sp3d2

This structure reflects the bonding and geometry of BrF5 as derived from VSEPR theory and the hybridization concept.

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