Question

How do you draw the lewis structure for ${\mathrm{NO}}_2$?

Answer 1

Lewis dot structure:

1. A Lewis Structure, also known as an Electron Dot Structure, is a simplified representation of a molecule's valence shell electrons. It describes the arrangement of valence electrons around particular atoms in a molecule.
2. Electronic configuration of nitrogen$=1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^3$ and electronic configuration of oxygen$=1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^4$.
3. Number of valence electrons in nitrogen $=5$ and number of valence electrons in oxygen$=6$ but in ${\mathrm{NO}}_2$ there are two oxygen so the total number of valence electrons of oxygen$=6\times 2\Rightarrow 12$
4. The total number of valence electrons in ${\mathrm{NO}}_2=12+5\Rightarrow 17$
5. Since the sum of valence electrons is an odd number, the octet of the central atom which is the N atom here cannot be completed.
6. Nitrogen being less electronegative will be in the center. So we will arrange these $17$electrons such that the octet is completed for oxygen leaving an electron on nitrogen. The dots in the structure represent electrons.
7. It is an odd electron molecule.