What type of molecular structure does SF6 exhibit?

• A. Linear
• B. Trigonal planar
• C. Octahedral
• D. Tetrahedral

Answer: (C)

SF6, or sulfur hexafluoride, exhibits an octahedral molecular structure. This is due to the presence of six fluorine atoms symmetrically surrounding a central sulfur atom. In the octahedral geometry, the bond angles are 90 degrees, and the arrangement allows for optimal spatial separation between electron pairs around the sulfur atom, minimizing repulsion according to VSEPR (Valence Shell Electron Pair Repulsion) theory.

The reason for this geometry stems from the sulfur atom’s ability to utilize d-orbitals for bonding, which is particularly notable in compounds where sulfur can expand its valence shell beyond the typical octet. In SF6, there are six bonding pairs formed between the sulfur and fluorine atoms, contributing to the octahedral shape.

Other structures do not accurately describe SF6:

• A linear structure would imply that the molecule only has two bonded atoms in a straight line, which is not the case here.

• Trigonal planar would suggest three atoms bonded to the central atom in a single plane, again not applicable since there are six fluorine atoms.

• Tetrahedral would imply four atoms are surrounding the central atom forming a shape with a specific geometry, which doesn't apply here as there is no planar