Chapter 2, Problem 2.56E

(a)

Interpretation Introduction

Interpretation:

Lewis structure of ${\text{NO}}_{\text{3}}{}^{-}$, ${\text{NO}}_2{}^{-}$ , ${\text{PO}}_4{}^{3-}$ and ${\text{HPO}}_3{}^{2-}$ to be drawn.

Concept Introduction:

Lewis structures represent covalent bonds and describe valence electrons configuration of atoms. The covalent bonds are depicted by lines and unshared electron pairs by pairs of dots. The sequence to write Lewis structure of some molecule is given as follows:

• The central atom is identified and various other atoms are arranged around it. This central atom so chosen is often the least electronegative.
• Total valence electrons are estimated for each atom.
• single bond is first placed between each atom pair.
• The electrons left can be allocated as unshared electron pairs or as multiple bonds around the symbol of the element to satisfy the octet (or duplet) for each atom.
• Add charge on the overall structure in case of polyatomic cation or anion.

(a)

Interpretation Introduction

Interpretation:

The reason behind phosphate ions found as connected chains in ATP while nitrate ions do not found as connected chains have to be explained.

Concept Introduction:

The table that relates the steric number with hybridization is as follows:

$\begin{array}{cc}\text{Steric Number}& \text{Type of Hybridisation}\\ 2& \text{sp}\\ 3& {\text{sp}}^2\\ 4& {\text{sp}}^3\\ 5& {\text{sp}}^3\text{d}\\ 6& {\text{sp}}^3{\text{d}}^2\end{array}$