Determine the molecular geometry about each interior atom of N2H2
The correct answer and explanation is:
The molecular geometry of N₂H₂ (hydrazine) involves understanding the bonding and the electron pair geometry around each atom. Hydrazine has a central nitrogen-nitrogen single bond with two hydrogen atoms attached to each nitrogen.
- Nitrogen Atoms (N):
Each nitrogen atom in N₂H₂ is bonded to two other atoms: one hydrogen atom and the other nitrogen atom. Additionally, nitrogen has one lone pair of electrons. For the nitrogen atoms, the electron-pair geometry is trigonal planar (due to three regions of electron density: two bonds and one lone pair). However, due to the lone pair, the actual molecular geometry is bent (or angular), which is typical for molecules with lone pairs. - Hydrogen Atoms (H):
Each hydrogen atom is bonded to a nitrogen atom. The molecular geometry around each hydrogen atom is linear since each hydrogen is connected by a single bond to the nitrogen atom.
Explanation:
- Electron Pair Geometry vs Molecular Geometry:
The electron-pair geometry around the nitrogen atoms in N₂H₂ is trigonal planar because there are three electron regions (two bonding pairs with hydrogen and nitrogen, and one lone pair). The lone pair causes a slight distortion in the molecular geometry, leading to a bent structure instead of a linear one. - Bond Angles:
The ideal bond angle for a trigonal planar geometry is 120°, but due to the lone pair on nitrogen, the actual bond angles between the nitrogen atoms and the hydrogen atoms will be slightly less than 120°. - Hybridization:
Each nitrogen atom in N₂H₂ undergoes sp² hybridization because it forms three regions of electron density (two sigma bonds with hydrogen and nitrogen and one lone pair of electrons).
In summary, the molecular geometry of N₂H₂ involves bent structures around each nitrogen atom due to the lone pairs of electrons, while the geometry around each hydrogen atom remains linear. The overall structure of the molecule is planar with a slight distortion from the lone pairs on nitrogen.