The Lewis diagram for NOBr is: Br The electron-pair geometry around the N atom in NOBr is: There is/are lone pair(s) around the central atom. So the geometry of NOBr is: The Lewis diagram for NOF is: 6-N=& The electron-pair geometry around the atom in NOF is: There is/are lone pair(s) around the central atom, so the geometry of NOF is:
The Lewis diagram for NOBr is: Br The electron-pair geometry around the N atom in NOBr is: There is/are lone pair(s) around the central atom. So the geometry of NOBr is: The Lewis diagram for NOF is: 6-N=& The electron-pair geometry around the atom in NOF is: There is/are lone pair(s) around the central atom, so the geometry of NOF is:
The Correct Answer and Explanation is:
Correct Answers
1. NOBr:
- Lewis diagram:
:Br–N=O
(with a lone pair on N) - Electron-pair geometry around the N atom: Trigonal planar
- There is/are lone pair(s) around the central atom: 1
- Molecular geometry of NOBr: Bent
2. NOF:
- Lewis diagram:
F–N=O
(with a lone pair on N) - Electron-pair geometry around the N atom: Trigonal planar
- There is/are lone pair(s) around the central atom: 1
- Molecular geometry of NOF: Bent
Explanation
To determine molecular geometry, we start with the Lewis structures of the molecules. For both NOBr and NOF, nitrogen (N) is the central atom, bonded to oxygen (O) and either bromine (Br) or fluorine (F).
1. NOBr:
Nitrogen has 5 valence electrons. It forms a double bond with oxygen (which prefers to form two bonds to complete its octet) and a single bond with bromine (a halogen, which usually forms one bond). After bonding, nitrogen has one lone pair remaining. This gives a total of three regions of electron density (a double bond, a single bond, and a lone pair), which corresponds to a trigonal planar electron geometry according to VSEPR theory. However, because one region is a lone pair, the actual molecular geometry is bent. The lone pair pushes the bonding atoms slightly closer together, resulting in a bond angle slightly less than 120°.
2. NOF:
Similar to NOBr, NOF has nitrogen at the center bonded to fluorine and oxygen. Nitrogen again forms a double bond with oxygen and a single bond with fluorine. It also retains one lone pair. This leads to three regions of electron density, just like in NOBr. Therefore, the electron-pair geometry is trigonal planar, but the molecular geometry is bent due to the presence of the lone pair.
In both molecules, the lone pair on nitrogen distorts the shape away from perfect trigonal planar geometry. The bent molecular shape affects the polarity of the molecules, making both polar, with uneven electron distribution across the molecule.
