12.2 Method of predicting the Hybrid state of the central atom in covalent molecules of polyatomic ions

  Chemical Bonding and Molecular Structure

    1.0 Ionic Bond or Electrovalent Bond
    2.0 Lattice Energy
    3.0 Characteristics of Electrovalent Compounds
    4.0 Covalent Bond (By Mutual Sharing of Electrons)
    5.0 Characteristics of Covalent Compounds
    6.0 Fajan’s Rule
    7.0 Hydrogen Bonding
    8.0 Coordinate Bond
    9.0 Valence Shell Electron Pair Repulsion (VSEPR) Theory
    10.0 Valence Bond Theory
    11.0 Sigma and Pi Bonds ($\sigma $ and $\pi $ Bonds)
    12.0 Hybridisation
    13.0 Molecular Orbital Theory

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12.2 Method of predicting the Hybrid state of the central atom in covalent molecules of polyatomic ions

The hybrid state of the central atom in similar covalent molecule or polyatomic ion can be predicted by using the generalized formula as described below:

Simple Molecule	Polyatomic Anion	Poyatomic Cation
$X = \frac{1}{2}\left[ {V + G} \right]$	$X = \frac{1}{2}\left[ {V + G + a} \right]$	$X = \frac{1}{2}\left[ {V + G - c} \right]$

In the above formulae,

$V=$ Number of monovalent atoms or groups attached to the central atom

$G=$ Number of outer shell electrons in ground state of the central atom

$a=$ Magnitude of charge on anion

$c=$ Magnitude of charge on cation

Calculate the value of $X$ and decide the hybrid state of central atom as follows :

$X$	$2$	$3$	$4$	$5$	$6$	$7$
Hybrid state	$sp$	$sp^2$	$sp^3$	$sp^3d$	$sp^3d^2$	$sp^3d^3$