Chapter 18, Problem 11A

(a)

Interpretation Introduction

Interpretation: The oxidation state of all atoms in ${\text{HNO}}_{\text{3}}$ needs to be determined.

Concept Introduction: Oxidation state indicates the number assigned to an element in a compound, which indicates the number of electrons transfer by the atom of that element.

It can be calculated with the help of standard oxidation states of certain elements like halogens with -1 oxidation state, alkali metals with +1 and alkaline earth metals with +2 oxidation state whereas O shows -2 oxidation state.

Answer to Problem 11A

• H = +1
• O = -2
• N = +5

Explanation of Solution

Let’s assume oxidation state of N = x

H = +1

O = -2

  $\begin{array}{l}{\text{HNO}}_{\text{3}}\\ (1\times +1)+x+(3\times -2)=0\\ 1+x-6=0\\ x=+5\end{array}$

(b)

Interpretation Introduction

Interpretation: The oxidation state of all atoms in ${\text{HPO}}_{\text{4}}^{\text{2-}}$ needs to be determined.

Concept Introduction: Oxidation state indicates the number assigned to an element in a compound, which indicates the number of electrons transfer by the atom of that element.

It can be calculated with the help of standard oxidation states of certain elements like halogens with -1 oxidation state, alkali metals with +1 and alkaline earth metals with +2 oxidation state whereas O shows -2 oxidation state.

Answer to Problem 11A

• H = +1
• O = -2
• P = +5

Explanation of Solution

Let’s assume oxidation state of P = x

H = +1

O = -2

  $\begin{array}{l}{\text{HPO}}_{\text{4}}^{\text{2-}}\\ (1\times +1)+x+(4\times -2)=-2\\ 1+x-8=-2\\ x=7-2=+5\end{array}$

(c)

Interpretation Introduction

Interpretation: The oxidation state of all atoms in ${\text{HSO}}_{\text{4}}^{\text{-}}$ needs to be determined.

Concept Introduction: Oxidation state indicates the number assigned to an element in a compound, which indicates the number of electrons transfer by the atom of that element.

It can be calculated with the help of standard oxidation states of certain elements like halogens with -1 oxidation state, alkali metals with +1 and alkaline earth metals with +2 oxidation state whereas O shows -2 oxidation state.

Answer to Problem 11A

• H = +1
• O = -2
• S = +6

Explanation of Solution

Let’s assume oxidation state of S = x

H = +1

O = -2

  $\begin{array}{l}{\text{HSO}}_{\text{4}}^{\text{-}}\\ (1\times +1)+x+(4\times -2)=-1\\ 1+x-8=-1\\ x=7-1=+6\end{array}$

(d)

Interpretation Introduction

Interpretation: The oxidation state of all atoms in ${\text{O}}_{\text{2}}^{\text{2-}}$ needs to be determined.

Concept Introduction: Oxidation state indicates the number assigned to an element in a compound, which indicates the number of electrons transfer by the atom of that element.

It can be calculated with the help of standard oxidation states of certain elements like halogens with -1 oxidation state, alkali metals with +1 and alkaline earth metals with +2 oxidation state whereas O shows -2 oxidation state.

Answer to Problem 11A

• O = -1

Explanation of Solution

Let’s assume oxidation state of O = x

  $\begin{array}{l}{\text{O}}_{\text{2}}^{\text{2-}}\\ 2x=-2\\ x=-1\end{array}$