For the molecule SeO2 determine the following:
Molecular geometry
Electron domain geometry
Hybridization
Bond angle
The correct answer and explanation is :
For the molecule SeO₂ (selenium dioxide), we need to determine the following:
Molecular Geometry:
The molecular geometry of SeO₂ is linear. This is because SeO₂ has two oxygen atoms double-bonded to the central selenium atom, with no lone pairs of electrons on the selenium atom. The two bonds are arranged in a straight line, creating a linear molecular shape.
Electron Domain Geometry:
The electron domain geometry is determined by considering the regions of electron density (bonding and lone pairs) around the central atom. In SeO₂, there are two double bonds between selenium and oxygen, meaning there are two regions of electron density. Since there are no lone pairs on the central selenium atom, the electron domain geometry is linear as well.
Hybridization:
To determine the hybridization, we need to assess the number of electron domains around the central atom. Since there are two regions of electron density (the two Se=O bonds), the hybridization of the central selenium atom is sp. This is because sp hybridization corresponds to two electron domains, which align with the linear shape of the molecule.
Bond Angle:
In a linear geometry, the bond angle between the two bonding regions is 180°. This is the angle that maximizes the distance between the electron domains, which is typical for molecules with sp hybridization.
Explanation:
SeO₂ consists of a central selenium atom bonded to two oxygen atoms through double bonds. Selenium, in its ground state, has six valence electrons. Each oxygen atom forms a double bond with selenium, contributing two electrons to each bonding region. The presence of two bonding regions and no lone pairs on the selenium atom results in a linear shape, both for the molecular geometry and the electron domain geometry. The hybridization of selenium is sp, as there are two regions of electron density around the atom, corresponding to the linear molecular structure. This geometry ensures that the bond angle is 180°, minimizing repulsion between the electron pairs. Thus, the SeO₂ molecule has a linear structure with 180° bond angles.