What is the state of hybridization of carbon in CO32- ion?
The Correct Answer and Explanation is:
The carbon atom in the carbonate ion, CO₃²⁻, has a state of sp² hybridization.
Explanation:
In the CO₃²⁻ ion, the carbon is bonded to three oxygen atoms. The ion has a trigonal planar geometry, meaning the bond angles between the atoms are approximately 120°, which suggests that the central atom, carbon, is sp² hybridized. Here’s why:
- Electron Pair Geometry and Bonding:
Carbon in CO₃²⁻ forms three sigma bonds with the oxygen atoms, which are distributed evenly in a trigonal planar shape. This geometry is consistent with the sp² hybridization, which involves the mixing of one s orbital and two p orbitals from carbon to form three sp² hybrid orbitals. These hybrid orbitals form sigma bonds with the oxygen atoms. - Delocalized Electrons:
The carbonate ion has resonance structures, meaning the double bond between carbon and one oxygen alternates between the three oxygen atoms. This delocalization of electrons over the three oxygen atoms further supports the idea of sp² hybridization. The third unhybridized p orbital on carbon is involved in the formation of a pi bond with oxygen atoms, allowing for the resonance of the ion. - Bond Angles:
The ideal bond angle for sp² hybridization is 120°, which matches the observed geometry of the CO₃²⁻ ion, confirming that the carbon atom in the ion is sp² hybridized.
Thus, the sp² hybridization allows for the correct electron distribution and resonance that stabilizes the carbonate ion.
