Molecules having one lone pair and three bond pairs have geometrical shape
Correct answer: C. Trigonal pyramidal
- A. Bent or angular
- B. Trigonal
- C. Trigonal pyramidal
- D. Trigonal planar
Explanation
Four regions of electron density arrange themselves tetrahedrally, but only the three bonded atoms are visible, so the shape is a pyramid, as in ammonia with its bond angle of about 107 degrees. Trigonal planar at 120 degrees would require three bond pairs and no lone pair, as in boron trifluoride, which is the trap here. A bent shape comes from two bond pairs with two lone pairs, as in water.
This question appeared on the UHS MDCAT 2025 paper, which you can sit online with every answer explained.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? support@testustad.com
About VSEPR Theory
Valence shell electron pair repulsion theory predicts molecular shape by arranging bonding pairs and lone pairs around a central atom to minimize repulsion. Questions cover linear, trigonal planar, tetrahedral, trigonal bipyramidal and octahedral electron geometries, bond angles and distortions caused by lone pairs. Electron geometry is not always the same as molecular shape.
Practise Chemical Bonding
964 free Chemical Bonding MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More VSEPR Theory questions
Which species is linear?
The number of lone pairs on the central atom in a water molecule is
The shape of the sulphur hexafluoride molecule, SF6, is
I3( Tri-iodine) has shape_________?
The number of lone pairs in XeOF4 is_________?
According to VESPR Model the geometry of molecule having 5 bond pair in outer most shell will be __________________?