Question

Which of the following statements regarding the structure of $SOC{l_2}$ is not correct ?
( A ) The sulphur is $s{p^3}$ hybridised and it has a tetrahedral shape .
( B ) The sulphur is $s{p^3}$ hybridised and it has a trigonal pyramid shape .
( C ) The oxygen – sulphur bond is p$\pi$ – d$\pi$ bond .
( D ) It contains one lone pair of electrons in the $s{p^3}$ hybrid orbital of sulphur .

Answer 1

As three atoms are bonded to the sulphur atom, we can say that the sulphur atom is $s{p^3}$ hybridized.And by referring to the shapes of atoms of different hybridization, it’s a trigonal pyramid shape. The shape and geometry of the molecule are defined by minimum repulsion.
For 3 electron pairs, the shape is trigonal pyramidal.

Complete step by step solution:
First, we consider, option ( A )
The $SOC{l_2}$ molecule is $s{p^3}$ hybridized.
The formula for finding hybridization of molecules is
Hybridization $= \dfrac{1}{2}\left( {V + H - C + A} \right)$
Here, V $=$ VALENCE ELECTRONS IN CENTRAL METAL ATOM
H $=$ Number of monovalent atom attached to the central metal atom
C $=$ Cation charge
A $=$ Anion charge
Substituting the values for $SOC{l_2}$,
$\Rightarrow$Hybridization $=$ $\dfrac{1}{2}$( 6 $+$2 $+$0 $+$0 )
$=$ $\dfrac{1}{2}$( 8 )
$=$4
Hence, the hybridization of $SOC{l_2}$is $s{p^3}$
Now, the structure of $SOC{l_2}$ is a trigonal planar because of the electron densities of 2 chlorine atoms and 1 oxygen atom, as given in the image.

Hence, option ( A ) is incorrect
For option ( B ),
The statement is true, as proved above that the sulphur is $s{p^3}$ hybridized and it has a trigonal pyramid shape.
Hence, option ( B ) is correct
For option ( C ),
The lone pair of p orbital back bonds with that of d orbital of central atom sulphur.
Hence, option ( C ) is correct
For option ( D ),
The electronic configuration of the sulphur atom is
1${s^2}$ 2${s^2}$ 2${p^6}$ 3${s^2}$ 3${p^4}$
The 4 valence electrons of sulphur bond with 2 chlorine atoms and 1 oxygen atom leaving behind 2 valence electrons out of 6
Hence, the sulphur atom contains 1 lone pair of electrons
Hence, option ( D ) is correct
So, The correct option is ( A ) - The sulphur is $s{p^3}$ hybridized and it has a tetrahedral shape.

Note: The geometry of $SOC{l_2}$ is due to the lone pair effect. The VSEPR Theory ( Valence Shell Electron Pair Repulsion ) gives the geometry and shape of molecules.
According to the VSEPR Theory the bond angle between oxygen, sulphur and chlorine are $106^\circ$and between chlorine, sulphur, chlorine is $96^\circ$ respectively.