What word or two-word phrase best describes the shape of the nitrosyl hydride ( hno ) molecule?
The Correct Answer and Explanation is:
The shape of the nitrosyl hydride (HNO) molecule can best be described as bent or V-shaped.
Explanation:
To understand the shape of the HNO molecule, we need to examine its molecular structure and apply the principles of molecular geometry, which can be determined using the valence shell electron pair repulsion (VSEPR) theory.
- Molecular Composition: The nitrosyl hydride (HNO) molecule consists of three atoms: one hydrogen (H), one nitrogen (N), and one oxygen (O). The central atom in the molecule is nitrogen, which is bonded to the hydrogen atom and the oxygen atom.
- Electron Pairs and Bonding:
- Nitrogen has five valence electrons, while oxygen has six, and hydrogen contributes one electron.
- Nitrogen forms a single bond with hydrogen and a double bond with oxygen.
- Oxygen has a lone pair of electrons in addition to the two electrons involved in the double bond with nitrogen.
- Electron Domain Count: According to the VSEPR theory, we count the electron domains around the central nitrogen atom. The nitrogen atom is involved in two bonding regions (one with hydrogen and one with oxygen) and has one lone pair of electrons. Therefore, nitrogen has three electron domains in total.
- Molecular Geometry: With three electron domains, the idealized geometry around nitrogen is trigonal planar. However, the lone pair of electrons on nitrogen exerts a repulsive force, causing the bonding atoms (hydrogen and oxygen) to be pushed closer together. This results in a molecular shape that is not flat, but rather bent, as the lone pair of electrons creates an angle between the bonds.
- Bond Angle: The bond angle in a bent geometry is slightly less than 120° (typically around 115°), which is characteristic of molecules with three regions of electron density and one lone pair.
Thus, the bent or V-shaped description accurately reflects the geometry of the HNO molecule.