determine the molecular geometry, or shape, of ClO2 a. octahedral b. tetrahedral c. trigonal bipyramidal d. trigonal planar e. t-shaped f. bent
The Correct Answer and Explanation is :
The molecular geometry of chlorine dioxide (ClO₂) is bent.
Explanation:
To determine the molecular geometry of ClO₂, we first need to consider its Lewis structure and the arrangement of its electron pairs. Chlorine (Cl) is the central atom in this molecule, bonded to two oxygen (O) atoms.
- Valence Electrons: Chlorine has seven valence electrons, and each oxygen has six. Therefore, for ClO₂, the total number of valence electrons is:
- ( 7 \text{ (from Cl)} + 6 \times 2 \text{ (from 2 O)} = 19 \text{ valence electrons} )
- Lewis Structure: In the Lewis structure, chlorine forms two single bonds with each oxygen atom. After forming these bonds, chlorine is left with one unshared electron pair, while each oxygen has two lone pairs. The structure can be represented as follows:
O
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Cl
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O- Electron Geometry: To determine the molecular geometry, we need to analyze the arrangement of electron pairs around the central chlorine atom. Chlorine has:
- 2 bonded pairs (from Cl–O bonds)
- 1 lone pair This results in a total of three regions of electron density (2 bonding pairs + 1 lone pair).
- VSEPR Theory: According to the Valence Shell Electron Pair Repulsion (VSEPR) theory, the arrangement of three regions of electron density corresponds to a trigonal planar electron geometry. However, the presence of the lone pair alters the shape of the molecule.
- Molecular Shape: The lone pair pushes down on the bonded pairs, resulting in a bent molecular shape. The bond angle is approximately 117 degrees due to the repulsion caused by the lone pair, which is slightly less than the ideal angle of 120 degrees found in a perfect trigonal planar arrangement.
In conclusion, due to the arrangement of two bonding pairs and one lone pair, the molecular geometry of chlorine dioxide (ClO₂) is classified as bent.