VSEPR Quiz
Questions: 16 · 10 minutes
1. Sulfur in SF₆ has six bonding regions and no lone pairs. Which molecular geometry does VSEPR predict?
Octahedral
Trigonal bipyramidal
Square pyramidal
Hexagonal planar
2. A BF₃ molecule has three bonding regions and no lone pairs on boron. Which geometry follows from this arrangement?
Trigonal planar
Tetrahedral
Trigonal pyramidal
Bent
3. Why is the H–O–H bond angle in water smaller than the ideal tetrahedral angle?
Lone pairs occupy more space and repel bonding regions more strongly than bonding pairs do.
O–H bonds repel more strongly than oxygen's lone pairs do.
Hydrogen atoms form an additional bond with each other.
The oxygen atom has only two electron domains.
4. Phosphorus in PCl₅ is surrounded by five bonding regions and no lone pairs. What molecular shape is predicted?
Square pyramidal
Trigonal bipyramidal
Seesaw
Octahedral
5. CH₄ has an ideal bond angle of about 109.5°. How should the H–N–H angle in NH₃ compare, given nitrogen's lone pair?
It should be larger because a lone pair pulls the bonds apart.
It should become 90° because NH₃ has three hydrogen atoms.
It should remain exactly 109.5° because both species have four electron domains.
It should be smaller because the lone pair compresses the bonding regions.
6. A Lewis structure for CH₄ has four C–H bonds and no lone pairs on carbon. What molecular shape does VSEPR predict?
Square planar
Trigonal pyramidal
Trigonal planar
Tetrahedral
7. In each resonance form of nitrate, NO₃⁻, the central nitrogen has three bonding regions and no lone pairs. What shape should be predicted around nitrogen?
Trigonal pyramidal
T-shaped
Trigonal planar
Tetrahedral
8. The central iodine in I₃⁻ has two bonding regions and three lone pairs, represented as AX₂E₃. What is the molecular shape of the ion?
Bent
T-shaped
Linear
Trigonal bipyramidal
9. After drawing H₂O with two O–H bonds and two lone pairs on oxygen, which molecular shape should you assign?
Linear
Bent
Trigonal planar
Tetrahedral
10. Carbon dioxide has two electron regions around its central carbon because each C=O double bond counts as one region. What is its molecular shape?
Bent
T-shaped
Trigonal planar
Linear
11. What central idea does VSEPR theory use to predict molecular geometry?
Atoms arrange themselves so every bond has the same polarity.
Electron regions around a central atom arrange themselves to minimize repulsions.
Molecular shape is determined only by the number of atoms present.
Bonded atoms occupy positions based primarily on their atomic masses.
12. XeF₄ has four bonding regions and two lone pairs around xenon. The six regions are octahedrally arranged, with the lone pairs opposite each other. What is the molecular shape?
Tetrahedral
Square pyramidal
Square planar
Trigonal bipyramidal
13. In NH₃, nitrogen has three bonding regions and one lone pair. What is its electron-domain geometry?
Trigonal pyramidal
Trigonal planar
Tetrahedral
Bent
14. How is the steric number of a central atom determined for VSEPR purposes?
Count its bonding regions and lone pairs, treating each multiple bond as one region.
Add the number of valence electrons to the number of bonded atoms.
Count every individual bond line and subtract the number of lone pairs.
Count only the atoms attached to the central atom.
15. The central chlorine in ClF₃ has three bonding regions and two lone pairs. What molecular shape does this produce?
Trigonal pyramidal
Trigonal planar
Seesaw
T-shaped
16. In SF₄, sulfur has four bonding regions and one lone pair. Which molecular shape results from this five-domain arrangement?
Tetrahedral
Seesaw
Trigonal pyramidal
Square planar