What is the molecular geometry of CO2 ?
A tetrahedral
B trigonal planar
C linear
D trigonal pyramidal
E bent
The Correct Answer and Explanation is :
The correct answer is C) linear.
Explanation:
The molecular geometry of carbon dioxide (CO₂) can be understood by examining its molecular structure and the arrangement of its atoms. CO₂ consists of one carbon atom (C) and two oxygen atoms (O). The central carbon atom is bonded to the two oxygen atoms through double bonds, which can be represented as O=C=O.
To determine the molecular geometry, we can use the Valence Shell Electron Pair Repulsion (VSEPR) theory. According to this theory, the shape of a molecule is determined by the repulsion between electron pairs in the valence shell of the central atom. In CO₂, the carbon atom has four valence electrons, while each oxygen atom has six valence electrons. The carbon atom forms two double bonds, resulting in a total of four shared electron pairs around the carbon.
Since there are no lone pairs of electrons on the central carbon atom, the two double bonds are the only electron groups. The arrangement of these two electron groups is linear, as they are positioned at a bond angle of 180 degrees to minimize repulsion. This linear arrangement leads to the molecular geometry being classified as linear as well.
The linear geometry of CO₂ also has significant implications for its physical and chemical properties. For example, the linear shape results in a nonpolar molecule, despite the polar bonds (C=O). This nonpolarity is due to the symmetrical arrangement of the polar bonds, causing the dipole moments to cancel each other out. Consequently, CO₂ does not exhibit strong intermolecular forces, contributing to its gaseous state at room temperature.
In summary, the molecular geometry of carbon dioxide is linear due to the arrangement of the double bonds and the absence of lone pairs on the central carbon atom, leading to a bond angle of 180 degrees.