The shape of the boron trifluoride molecule, BF3, is
Correct answer: D. trigonal planar with bond angles of 120 degrees
- A. pyramidal
- B. bent
- C. tetrahedral
- D. trigonal planar with bond angles of 120 degrees
Explanation
Boron forms three bonds and has no lone pair, so the three electron regions lie flat at 120 degrees, and the molecule is an exception to the octet rule with only six electrons round the central atom. That electron deficiency is why boron trifluoride readily accepts a lone pair and acts as a Lewis acid. Ammonia looks similar on paper but is pyramidal because of its lone pair.
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
The bond angle in a water molecule is about 104.5 degrees rather than 109.5 degrees because
The shape of the ammonia molecule, NH3, is
According to VSEPR theory, the shape of a molecule is decided by
The shape of the methane molecule and the carbon dioxide molecule are respectively
The bond angle in a molecule of methane, ammonia and water decreases in the order 109.5, 107 and 104.5 degrees because
According to VSEPR theory, a molecule with four bond pairs and no lone pairs on the central atom is