Chapter 9, Problem 9.107QE

(a)

Interpretation Introduction

Interpretation:

The equation for the reaction of uranium with ${\text{ClF}}_{\text{3}}$ has to be determined. Also, the equation for the reaction of $\text{Pu}$ with ${\text{ClF}}_{\text{3}}$ has to be determined.

Concept Introduction:

An equation that represents the symbol and formula of reactants and products of the reaction is known as the chemical equation for a reaction.

(b)

Interpretation Introduction

Interpretation:

The Lewis structure of ${\text{ClF}}_{\text{3}}$ has to be determined. Also, the unusual thing about the structure of ${\text{ClF}}_{\text{3}}$ has to be identified.

Concept Introduction:

Steps to write Lewis structures are as follows:

1. The skeleton structure with single bonds between all bonded atoms has to be written

2. Sum the valence electrons of the atoms in the molecule.

(a) For cations, one electron is subtracted for each positive charge.

(b) For anions, one electron is added for each negative charge.

3. Subtract two electrons from total number of valence electrons for each bond in the skeleton structure.

4. Count the number of electrons required to satisfy the octet rule for each atom in the structure. If the number of electrons needed is less than the number remaining, add one bond for every two electrons needed between atoms to attain an octet.

5. The remaining electrons are placed as lone pairs on atoms that need them to satisfy the octet rule.

The formula to calculate formal charge of atom is,

  $\text{Formal}\text{charge}=\left(\begin{array}{l}\text{number}\text{of}\\ \text{valence}\\ \text{electrons}\end{array}\right)-\left(\left(\begin{array}{l}\text{number}\text{of}\\ \text{lone pairs of}\\ \text{electrons}\end{array}\right)+\left(\frac{1}{2}\right)\left(\begin{array}{l}\text{number}\text{of}\\ \text{shared}\\ \text{electrons}\end{array}\right)\right)$        (1)

Some compounds exceed an octet around the central atom and are called as expanded valence shell molecule. The central atom belongs to third and fourth periods. In this, the molecule has electrons more than eight electrons in Lewis structure.

(c)

Interpretation Introduction

Interpretation:

The masses of the uranium and plutonium in the initial mixture have to be determined.

Concept Introduction:

Moleis the S.I. unit. The number of moles is the ratio of mass of the compound to molar mass of compound.

Molar mass is the sum of the total mass in grams of all the atoms that make a mole of a particular molecule that is the mass of one mole of a compound. Its S.I unit is g/mol.

The expression for number of moles is as follows:

  $\text{Number of moles}=\frac{\text{mass of the compound}}{\text{molar mass of the compound}}$        (1)