Chapter 8, Problem 30A

(a)

Interpretation Introduction

Interpretation: The given oxidation-reduction reaction needs to be balanced.

  ${\text{Fe}}_{\text{(s)}}{\text{ + S}}_{\text{(s) }}\stackrel{}{\to }{\text{ Fe}}_{\text{2}}{\text{S}}_{\text{3}}{}_{\text{(g)}}$

Concept Introduction: A chemical reaction can be described as the process of conversion of reactant molecules to product molecules by breaking and making of chemical bonds.

A balance chemical reaction contains same number of atoms at both sides of the chemical reaction.

Answer to Problem 30A

  ${\text{2 Fe}}_{\text{(s)}}{\text{ + 3 S}}_{\text{(s) }}\stackrel{}{\to }{\text{ Fe}}_{\text{2}}{\text{S}}_{\text{3}}{}_{\text{(g)}}$

Explanation of Solution

In a balance chemical equation, the number of atoms must be same at both sides. To balance a chemical reaction, coefficients must be added with the chemical formula to make it same at both sides.

Reactant	Product
Fe = 1→2	Fe = 2
S= 1→3	S = 3

Thus the balance chemical equation must be:

  ${\text{2 Fe}}_{\text{(s)}}{\text{ + 3 S}}_{\text{(s) }}\stackrel{}{\to }{\text{ Fe}}_{\text{2}}{\text{S}}_{\text{3}}{}_{\text{(g)}}$

(b)

Interpretation Introduction

Interpretation: The given oxidation-reduction reaction needs to be balanced.

  ${\text{Zn}}_{\text{(s)}}{\text{ + HNO}}_{\text{3}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ Zn(NO}}_{\text{3}}{\text{)}}_{{\text{2}}_{\text{(aq) }}}{\text{+ H}}_{\text{2}}{}_{\text{(g)}}$

Concept Introduction: A chemical reaction can be described as the process of conversion of reactant molecules to product molecules by breaking and making of chemical bonds.

A balance chemical reaction contains same number of atoms at both sides of the chemical reaction.

Answer to Problem 30A

  ${\text{Zn}}_{\text{(s)}}{\text{ + 2 HNO}}_{\text{3}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ Zn(NO}}_{\text{3}}{\text{)}}_{{\text{2}}_{\text{(aq) }}}{\text{+ H}}_{\text{2}}{}_{\text{(g)}}$

Explanation of Solution

In a balance chemical equation, the number of atoms must be same at both sides. To balance a chemical reaction, coefficients must be added with the chemical formula to make it same at both sides.

Reactant	Product
Zn = 1	Zn = 1
N= 1→2	N= 2
H=1→2	H=2
O =3→6	O = 6

Thus the balance chemical equation must be:

  ${\text{Zn}}_{\text{(s)}}{\text{ + 2 HNO}}_{\text{3}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ Zn(NO}}_{\text{3}}{\text{)}}_{{\text{2}}_{\text{(aq) }}}{\text{+ H}}_{\text{2}}{}_{\text{(g)}}$

(c)

Interpretation Introduction

Interpretation: The given oxidation-reduction reaction needs to be balanced.

  ${\text{Sn}}_{\text{(s)}}{\text{ + O}}_{\text{2}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ SnO}}_{\text{(s)}}$

Concept Introduction: A chemical reaction can be described as the process of conversion of reactant molecules to product molecules by breaking and making of chemical bonds.

A balance chemical reaction contains same number of atoms at both sides of the chemical reaction.

Answer to Problem 30A

  ${\text{2 Sn}}_{\text{(s)}}{\text{ + O}}_{\text{2}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ 2 SnO}}_{\text{(s)}}$

Explanation of Solution

In a balance chemical equation, the number of atoms must be same at both sides. To balance a chemical reaction, coefficients must be added with the chemical formula to make it same at both sides.

Reactant	Product
Sn = 1	Sn = 1
O =2→2	O = 2→2

Thus the balance chemical equation must be:

  ${\text{2 Sn}}_{\text{(s)}}{\text{ + O}}_{\text{2}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ 2 SnO}}_{\text{(s)}}$

(d)

Interpretation Introduction

Interpretation: The given oxidation-reduction reaction needs to be balanced.

  ${\text{K}}_{\text{(s)}}{\text{ + H}}_{\text{2}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ KH}}_{\text{(s)}}$

Concept Introduction: A chemical reaction can be described as the process of conversion of reactant molecules to product molecules by breaking and making of chemical bonds.

A balance chemical reaction contains same number of atoms at both sides of the chemical reaction.

Answer to Problem 30A

  ${\text{2 K}}_{\text{(s)}}{\text{ + H}}_{\text{2}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ 2 KH}}_{\text{(s)}}$

Explanation of Solution

In a balance chemical equation, the number of atoms must be same at both sides. To balance a chemical reaction, coefficients must be added with the chemical formula to make it same at both sides.

Reactant	Product
K = 1	K = 1
H =2→2	H = 1→2

Thus the balance chemical equation must be:

  ${\text{2 K}}_{\text{(s)}}{\text{ + H}}_{\text{2}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ 2 KH}}_{\text{(s)}}$

(e)

Interpretation Introduction

Interpretation: The givenoxidation-reduction reaction needs to be balanced.

  ${\text{Cs}}_{\text{(s)}}{\text{ + H}}_{\text{2}}{\text{O}}_{\text{(l) }}\stackrel{}{\to }{\text{ CsOH}}_{\text{(s)}}{\text{+ H}}_{\text{2}}{}_{\text{(g) }}$

Concept Introduction: A chemical reaction can be described as the process of conversion of reactant molecules to product molecules by breaking and making of chemical bonds.

A balance chemical reaction contains same number of atoms at both sides of the chemical reaction.

Answer to Problem 30A

  ${\text{2 Cs}}_{\text{(s)}}{\text{ + 2 H}}_{\text{2}}{\text{O}}_{\text{(l) }}\stackrel{}{\to }{\text{ 2 CsOH}}_{\text{(s)}}{\text{+ H}}_{\text{2}}{}_{\text{(g) }}$

Explanation of Solution

In a balance chemical equation, the number of atoms must be same at both sides. To balance a chemical reaction, coefficients must be added with the chemical formula to make it same at both sides.

Reactant	Product
Cs = 1	Cs = 1
H =2→4	H = 3→2
O = 1→2	O = 1→2

Thus the balance chemical equation must be:

  ${\text{2 Cs}}_{\text{(s)}}{\text{ + 2 H}}_{\text{2}}{\text{O}}_{\text{(l) }}\stackrel{}{\to }{\text{ 2 CsOH}}_{\text{(s)}}{\text{+ H}}_{\text{2}}{}_{\text{(g) }}$