Answer: 3
Explanation: Formula used for calculating the hybrid orbitals:
[tex]CO_3^{2-}:[/tex]
[tex]:{\text{Number of electrons}} =\frac{1}{2}[V+N-C+A][/tex]
where, V = number of valence electrons present in central atom i.e. carbon = 4
N = number of monovalent atoms bonded to central atom=0
C = charge of cation = 0
A = charge of anion = -2
[tex]{\text{Number of electrons}} =\frac{1}{2}[4+0-0+2]=3[/tex]
The number of electrons is 3 that means the hybridization will be [tex]sp^2[/tex] and the electronic geometry of the molecule will be trigonal planar which will be formed by three [tex]sp^2[/tex] hybrid orbitals.
