Question

Draw a Lewis structure for SO2 in which all atoms obey the octet rule. Show formal charges. Do not consider ringed structures.

Draw a Lewis structure for SO2 in which all atoms have a formal charge of zero. Explicitly showing the zero charges is optional. Do not consider ringed structures.

Answer 1

Concepts and reason

Calculate total number of valance electrons in ${\rm{S}}{{\rm{O}}_{\rm{2}}}$ and draw the Lewis structure that contains all the atoms with octet configuration.

Calculate formal charge by using the following formula.

$\begin{array}{l}\\{\rm{Formal charge of atom = Number of valance electrons}} - [{\rm{Number of unshared valance }}\\\\{\rm{ electrons + }}\frac{1}{2}{\rm{ Number of shared valance electrons]}}\\\end{array}$

Fundamentals

Lewis structure is a diagram that show bonding between atoms in a molecule and also shows lone pair of electrons present on the atoms.

Charge on an atom without considering electronegativity differences is called as formal charge.

Sulfur and oxygen atoms belong to Group 6A of the periodic table.

$\begin{array}{c}\\{\rm{Total valance electrons in S}}{{\rm{O}}_{\rm{2}}}{\rm{ = 6}}{{\rm{e}}^ - }{\rm{ + 2 \times 6}}{{\rm{e}}^ - }\\\\{\rm{ = 18 }}{{\rm{e}}^ - }\\\end{array}$

Connect all the atoms of the molecule with respect of their valances. Correct Lewis structure with octet of all the atoms is as follows:

Lewis structure with formal charges of zero is shown below.

Ans:

Lewis structure of with correct formal charges is as follows: