Chapter 9, Problem 9.92QE

(a)

Interpretation Introduction

Interpretation:

The element E in ${\text{EF}}_{\text{4}}{}^{-}$ that belongs to second period has to be determined.

Concept Introduction:

Second period has eight elements namely lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, and neon.

Formal charge is a charge of each atom in the structure. A formal charge is the electric charge of an atom in a molecule. The sum of formal charges on neutral species must zero.

The sum of the formal charges on an ion must equal the charge on the ion. Most Lewis structures have values of zero for the formal charges of the atoms.

The formula to calculate formal charge on an atom is as follows:

    $\text{Formal charge}=\left[\begin{array}{c}\left(\text{number of valence electrons in an atom}\right)\\ -\left(\text{number of lone pairs}\right)-\frac{1}{2}\left(\text{number of shared electrons}\right)\end{array}\right]$

(b)

Interpretation Introduction

Interpretation:

The element E in ${\text{EF}}_{\text{4}}{}^{+}$ that belongs to second period has to be determined.

Concept Introduction:

Refer to part (a)