Chapter 8, Problem 50A

(a)

Interpretation Introduction

Interpretation: The given reaction needs to be balanced and classified.

  ${\text{C}}_{\text{3}}{\text{H}}_{\text{8}}{\text{O}}_{\text{(l)}}{\text{ + O}}_{\text{2}}{}_{\text{(g) }}\stackrel{}{\to }{\text{ CO}}_{\text{2}}{}_{\text{(g)}}+{\text{H}}_{\text{2}}{\text{O}}_{\text{(g)}}$

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 50A

  ${\text{2 C}}_{\text{3}}{\text{H}}_{\text{8}}{\text{O}}_{\text{(l)}}{\text{ + 9 O}}_{\text{2}}{}_{\text{(g) }}\stackrel{}{\to }{\text{ 6 CO}}_{\text{2}}{}_{\text{(g)}}+8{\text{H}}_{\text{2}}{\text{O}}_{\text{(g)}}$

Combustion reaction

Explanation of Solution

In a balance chemical equation, the number of atoms of same elements 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
C= 3(6	C = 1(6
H =8(16	H = 2(16
O = 3(20	O=3( 20

Thus, the balance chemical equation must be:

  ${\text{2 C}}_{\text{3}}{\text{H}}_{\text{8}}{\text{O}}_{\text{(l)}}{\text{ + 9 O}}_{\text{2}}{}_{\text{(g) }}\stackrel{}{\to }{\text{ 6 CO}}_{\text{2}}{}_{\text{(g)}}+8{\text{H}}_{\text{2}}{\text{O}}_{\text{(g)}}$

In the given reaction, ${\text{C}}_{\text{3}}{\text{H}}_{\text{8}}\text{O}$ combust to ${\text{CO}}_{\text{2}}$ and ${\text{H}}_{\text{2}}\text{O}$ in the presence of ${\text{O}}_{\text{2}}$ thus it should be combustion reaction.

(b)

Interpretation Introduction

Interpretation: The given reaction needs to be balanced and classified.

  ${\text{HCl}}_{\text{(aq)}}{\text{ + AgC}}_{\text{2}}{\text{H}}_{\text{3}}{\text{O}}_{\text{2}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ AgCl}}_{\text{(s)}}+{\text{HC}}_{\text{2}}{\text{H}}_{\text{3}}{\text{O}}_{\text{2}}{}_{\text{(aq)}}$

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 50A

  ${\text{HCl}}_{\text{(aq)}}{\text{ + AgC}}_{\text{2}}{\text{H}}_{\text{3}}{\text{O}}_{\text{2}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ AgCl}}_{\text{(s)}}+{\text{HC}}_{\text{2}}{\text{H}}_{\text{3}}{\text{O}}_{\text{2}}{}_{\text{(aq)}}$

Double displacement reaction

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
Cl= 1(1	Cl= 1( 1
H = 4(4	H = 4 ( 4
O = 2(2	O=2(2
Ag = 1(1	Ag = 1(1

Thus, the balance chemical equation must be:

  ${\text{HCl}}_{\text{(aq)}}{\text{ + AgC}}_{\text{2}}{\text{H}}_{\text{3}}{\text{O}}_{\text{2}}{}_{\text{(aq) }}\stackrel{}{\to }{\text{ AgCl}}_{\text{(s)}}+{\text{HC}}_{\text{2}}{\text{H}}_{\text{3}}{\text{O}}_{\text{2}}{}_{\text{(aq)}}$

In the given reaction, ${\text{AgC}}_{\text{2}}{\text{H}}_{\text{3}}{\text{O}}_{\text{2}}$ and $\text{HCl}$ react to form AgCl and ${\text{HC}}_{\text{2}}{\text{H}}_{\text{3}}{\text{O}}_{\text{2}}$ . Since two times displacement occurs therefore it should be double displacement reaction.

(c)

Interpretation Introduction

Interpretation: The given reaction needs to be balanced and classified. ${\text{HCl}}_{\text{(aq)}}{\text{ + Al(OH)}}_{\text{3(s)}}\stackrel{}{\to }{\text{AlCl}}_{\text{3}}{}_{\text{(aq)}}+{\text{H}}_{\text{2}}{\text{O}}_{\text{(aq)}}$

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 50A

  ${\text{3 HCl}}_{\text{(aq)}}{\text{ + Al(OH)}}_{\text{3(s)}}\stackrel{}{\to }{\text{AlCl}}_{\text{3}}{}_{\text{(aq)}}+3{\text{H}}_{\text{2}}{\text{O}}_{\text{(aq)}}$

Acid-base or neutralization reaction which is an example of double displacement reaction.

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
Cl= 1(3	Cl= 3(3
H = 4 (6	H =2(6
O = 3(3	O=3( 3
Al = 1( 1	Al = 1( 1

Thus, the balance chemical equation must be:

  ${\text{3 HCl}}_{\text{(aq)}}{\text{ + Al(OH)}}_{\text{3(s)}}\stackrel{}{\to }{\text{AlCl}}_{\text{3}}{}_{\text{(aq)}}+3{\text{H}}_{\text{2}}{\text{O}}_{\text{(aq)}}$

In the given reaction, ${\text{Al(OH)}}_{\text{3(s)}}$ and $\text{HCl}$ react to form ${\text{AlCl}}_{\text{3}}$ and ${\text{H}}_{\text{2}}\text{O}$ . Here ${\text{Al(OH)}}_{\text{3(s)}}$ is base and $\text{HCl}$ is acid therefore it should be acid-base or neutralization reaction which is an example of double displacement reaction.

(d)

Interpretation Introduction

Interpretation: The given reaction needs to be balanced and classified.

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

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 50A

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

Acid-base or neutralization reaction which is an example of double displacement reaction.

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
H =2(4	H =2(4
O = 2(4	O= 3(4

Thus the balance chemical equation must be:

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

In the given reaction, ${\text{H}}_{\text{2}}{\text{O}}_{\text{2}}$ decomposed to two of it component therefore it should be decomposition reaction.

(e)

Interpretation Introduction

Interpretation: The given reaction needs to be balanced and classified.

  ${\text{N}}_{\text{2}}{\text{H}}_{\text{4}}{}_{\text{(l)}}{\text{+ O}}_{\text{2(g)}}\stackrel{}{\to }{\text{N}}_{\text{2}}{}_{\text{(g)}}{\text{+ H}}_{\text{2}}{\text{O}}_{\text{(g)}}$

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 50A

  ${\text{N}}_{\text{2}}{\text{H}}_{\text{4}}{}_{\text{(l)}}{\text{+ O}}_{\text{2(g)}}\stackrel{}{\to }{\text{N}}_{\text{2}}{}_{\text{(g)}}{\text{+ 2 H}}_{\text{2}}{\text{O}}_{\text{(g)}}$

Oxidation reaction.

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
H =2( 4	H =2( 4
O = 2( 4	O= 3( 4
N = 2(2	N =2(2

Thus, the balance chemical equation must be:

  ${\text{N}}_{\text{2}}{\text{H}}_{\text{4}}{}_{\text{(l)}}{\text{+ O}}_{\text{2(g)}}\stackrel{}{\to }{\text{N}}_{\text{2}}{}_{\text{(g)}}{\text{+ 2 H}}_{\text{2}}{\text{O}}_{\text{(g)}}$

In the given reaction, ${\text{N}}_{\text{2}}{\text{H}}_{\text{4}}$ reacts with oxygen to form nitrogen gas and water so it must be oxidation reaction.