Sulfur hexafluoride SF6 is a Lewis Structure Electron Geometry: Molecular Geometry: VSEPR Drawing Around Central Atom Single Bonds: AEN: Overall Polarity: e-groups Double Bonds: Polar Non Polar Triple Bonds: Angles: Lone Pairs:
The Correct Answer and Explanation is:
Correct Answers
- Lewis Structure: Central sulfur atom bonded to six fluorine atoms. Each fluorine has three lone pairs.
- Around Central Atom
- Single Bonds: 6
- Double Bonds: 0
- Triple Bonds: 0
- Lone Pairs: 0
- Electron Geometry: Octahedral
- Molecular Geometry: Octahedral
- VSEPR Drawing: SF₆ with six F atoms symmetrically arranged around the S atom in 3D (along x, y, z axes)
- e⁻ Groups: 6
- ΔEN (Electronegativity Difference): 3.98 – 2.58 = 1.40
- Bond Angles: 90°
- Overall Polarity: Nonpolar
Explanation (≈ 300 words) Sulfur hexafluoride (SF₆) is an example of a hypervalent molecule in which the central atom, sulfur, exceeds the octet rule. In its Lewis structure, sulfur forms six single bonds with fluorine atoms, resulting in 12 bonding electrons around sulfur. Since sulfur is in period 3, it has available d orbitals and can accommodate this expanded valence.
VSEPR (Valence Shell Electron Pair Repulsion) theory helps predict the shape of molecules by minimizing repulsion between electron groups around a central atom. In SF₆, there are six regions of electron density (six bonding pairs) and no lone pairs on the sulfur. This leads to an octahedral electron geometry. Because all the terminal atoms are the same and symmetrically arranged, the molecular geometry is also octahedral.
Each S–F bond angle is 90°, characteristic of the octahedral shape. Although S–F bonds are polar due to a moderate electronegativity difference (1.40), the molecule’s symmetry causes the dipoles to cancel. This makes SF₆ nonpolar overall.
The structural properties of SF₆ have practical implications. It is chemically inert and has high dielectric strength, making it valuable as an insulating gas in high-voltage equipment. However, it is also a potent greenhouse gas with a long atmospheric lifetime, which is why its use is strictly regulated.
In summary, SF₆ demonstrates how molecular geometry and symmetry govern physical properties like polarity. Despite highly polar bonds, the overall shape determines its behavior in both chemical and environmental contexts. Let me know if you’d like a VSEPR sketch or a comparison to similar molecules like IF₅ or XeF₄.
