Which molecular geometry best describes the shape of a hydrogen fluoride (HF) molecule?

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

Answer: (C)

Verified step by step guidance

1. Identify the central atom in the molecule. In hydrogen fluoride (HF), fluorine (F) is the central atom bonded to hydrogen (H).
2. Determine the number of atoms bonded to the central atom and the number of lone pairs on the central atom. HF has one hydrogen atom bonded to fluorine and three lone pairs on fluorine.
3. Recall that molecular geometry depends on the arrangement of bonded atoms and lone pairs around the central atom. Since there is only one bonded atom and lone pairs do not affect the shape in this case, the molecule's shape is determined by the bonded atoms.
4. Recognize that with only two atoms (H and F), the molecule is arranged in a straight line, which corresponds to a linear geometry.
5. Conclude that the molecular geometry of HF is linear because it consists of two atoms connected by a single bond with no additional bonded atoms to create angles.