Chapter 21, Problem 21.104QP

Interpretation Introduction

(a)

Interpretation:

The given equation has to be written complete and balanced

Concept Introduction:

Balancing the equation:

• There is a Law for conversion of mass in a chemical reaction i.e., the mass of total amount of the product should be equal to the total mass of the reactants.
• The concept of writing a balanced chemical reaction is depends on conversion of reactants into products.
• First write the reaction from the given information.
• Then count the number of atoms of each element in reactants as well as products.
• Finally obtained values could place it as coefficients of reactants as well as products.
• Loss of electron and loss of Hydrogen in a compound is oxidation - the compound is oxidized.  Gain of electron, gain of Oxygen in a compound is reduction - the compound is reduced.
• Oxidation reduction and reduction reaction occur simultaneously in same reaction.

To Write: The given equation complete and balanced.

Answer to Problem 21.104QP

The complete and balanced equation for the given equation is:

${\text{2KOH(aq) + MgCl}}_{\text{2}}\text{(aq)}\stackrel{}{\to }{\text{ Mg(OH)}}_2\text{(s) + 2KCl(aq)}$

Explanation of Solution

Given Equation:

${\text{KOH(aq) + MgCl}}_{\text{2}}\text{(aq)}\stackrel{}{\to }$

Complete Equation:

A complete equation will have same elements present on both sides of the equation.

The above equation can be completed by writing as follows,

${\text{KOH(aq) + MgCl}}_{\text{2}}\text{(aq)}\stackrel{}{\to }{\text{ Mg(OH)}}_2\text{(s) + KCl(aq)}$

Balancing the equation:

A balanced equation will have same elements and same number of atoms of each side of the reaction.

List the atoms of the equation in a table and check for the equal number of atoms present on either side of the reaction.

${\text{KOH(aq) + MgCl}}_{\text{2}}\text{(aq)}\stackrel{}{\to }{\text{ Mg(OH)}}_2\text{(s) + KCl(aq)}$

Reactant side	Atom	Product side
1	$\text{K}$	1
1	$\text{O}$	2
1	$\text{H}$	2
1	$\text{Mg}$	1
2	$\text{Cl}$	1

To balance the $\text{Cl, H and O}$ atom, multiply $\text{KOH}$ on the reactant side and $\text{KCl}$ on the product side by two.

${\text{2KOH(aq) + MgCl}}_{\text{2}}\text{(aq)}\stackrel{}{\to }{\text{ Mg(OH)}}_2\text{(s) + 2KCl(aq)}$

Again, list the atoms of the equation in a table and check for the equal number of atoms present on either side of the reaction.

Reactant side	Atom	Product side
2	$\text{K}$	2
2	$\text{O}$	2
2	$\text{H}$	2
1	$\text{Mg}$	1
2	$\text{Cl}$	2

The number of atoms on both sides of the reaction are same. Therefore, the above equation is a balanced one.

Hence, the complete and balanced form of the given equation is written as:

${\text{2KOH(aq) + MgCl}}_{\text{2}}\text{(aq)}\stackrel{}{\to }{\text{ Mg(OH)}}_2\text{(s) + 2KCl(aq)}$

Conclusion

The complete and balanced equation of the given equation is written as:

${\text{2KOH(aq) + MgCl}}_{\text{2}}\text{(aq)}\stackrel{}{\to }{\text{ Mg(OH)}}_2\text{(s) + 2KCl(aq)}$

Interpretation Introduction

(b)

Interpretation:

The given equation has to be written complete and balanced

Concept Introduction:

Balancing the equation:

• There is a Law for conversion of mass in a chemical reaction i.e., the mass of total amount of the product should be equal to the total mass of the reactants.
• The concept of writing a balanced chemical reaction is depends on conversion of reactants into products.
• First write the reaction from the given information.
• Then count the number of atoms of each element in reactants as well as products.
• Finally obtained values could place it as coefficients of reactants as well as products.
• Loss of electron and loss of Hydrogen in a compound is oxidation - the compound is oxidized.  Gain of electron, gain of Oxygen in a compound is reduction - the compound is reduced.
• Oxidation reduction and reduction reaction occur simultaneously in same reaction.

To Write: The given equation complete and balanced.

Answer to Problem 21.104QP

The complete and balanced equation of the given equation is:

${\text{Mg(s) + CuSO}}_{\text{4}}\text{(aq)}\stackrel{}{\to }{\text{ Cu(s) + MgSO}}_{\text{4}}(aq)$

Explanation of Solution

Given Equation:

${\text{Mg(s) + CuSO}}_{\text{4}}\text{(aq)}\stackrel{}{\to }$

Complete equation:

A complete equation will have same present on both sides of the equation.

The above equation can be completed by writing as follows,

${\text{Mg(s) + CuSO}}_{\text{4}}\text{(aq)}\stackrel{}{\to }{\text{ Cu(s) + MgSO}}_{\text{4}}(aq)$

Balancing the equation:

A balanced equation will have same elements and same number of atoms of each side of the reaction.

${\text{Mg(s) + CuSO}}_{\text{4}}\text{(aq)}\stackrel{}{\to }{\text{ Cu(s) + MgSO}}_{\text{4}}(aq)$

List the atoms of the equation in a table and check for the equal number of atoms present on either side of the reaction.

Reactant side	Atom	Product side
1	$\text{Cu}$	1
4	$\text{O}$	4
1	$\text{Mg}$	1
1	$\text{S}$	1

The number of atoms on both sides of the reaction are same. Therefore, the above equation is a balanced one.

Hence, the complete and balanced form of the given equation is written as:

${\text{Mg(s) + CuSO}}_{\text{4}}\text{(aq)}\stackrel{}{\to }{\text{ Cu(s) + MgSO}}_{\text{4}}(aq)$

Conclusion

The complete and balanced equation of the given equation is written as:

${\text{Mg(s) + CuSO}}_{\text{4}}\text{(aq)}\stackrel{}{\to }{\text{ Cu(s) + MgSO}}_{\text{4}}(aq)$

Interpretation Introduction

(c)

Interpretation:

The given equation has to be written complete and balanced

Concept Introduction:

Balancing the equation:

• There is a Law for conversion of mass in a chemical reaction i.e., the mass of total amount of the product should be equal to the total mass of the reactants.
• The concept of writing a balanced chemical reaction is depends on conversion of reactants into products.
• First write the reaction from the given information.
• Then count the number of atoms of each element in reactants as well as products.
• Finally obtained values could place it as coefficients of reactants as well as products.
• Loss of electron and loss of Hydrogen in a compound is oxidation - the compound is oxidized.  Gain of electron, gain of Oxygen in a compound is reduction - the compound is reduced.
• Oxidation reduction and reduction reaction occur simultaneously in same reaction.

To Write: The given equation complete and balanced.

Answer to Problem 21.104QP

The complete and balanced equation for the given equation is:

${\text{Sr(s) + 2H}}_{\text{2}}\text{O(l)}\stackrel{}{\to }{\text{ Sr(OH)}}_2{\text{(aq) + H}}_{\text{2}}\text{(g)}$

Explanation of Solution

Given Equation:

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

Complete Equation:

A complete equation will have same elements present on both sides of the equation.

The above equation can be completed by writing as follows,

${\text{Sr(s) + H}}_{\text{2}}\text{O(l)}\stackrel{}{\to }{\text{ Sr(OH)}}_2{\text{(aq) + H}}_{\text{2}}\text{(g)}$

Balancing the equation:

A balanced equation will have same elements and same number of atoms of each side of the reaction.

List the atoms of the equation in a table and check for the equal number of atoms present on either side of the reaction.

${\text{Sr(s) + H}}_{\text{2}}\text{O(l)}\stackrel{}{\to }{\text{ Sr(OH)}}_2{\text{(aq) + H}}_{\text{2}}\text{(g)}$

Reactant side	Atom	Product side
1	$\text{Sr}$	1
1	$\text{O}$	2
2	$\text{H}$	4

To balance the $\text{H and O}$ atom, multiply water on the reactant side by two.

${\text{Sr(s) + 2H}}_{\text{2}}\text{O(l)}\stackrel{}{\to }{\text{ Sr(OH)}}_2{\text{(aq) + H}}_{\text{2}}\text{(g)}$

Again, list the atoms of the equation in a table and check for the equal number of atoms present on either side of the reaction.

Reactant side	Atom	Product side
1	$\text{Sr}$	1
2	$\text{O}$	2
4	$\text{H}$	4

The number of atoms on both sides of the reaction are same. Therefore, the above equation is a balanced one.

Hence, the complete and balanced form of the given equation is written as:

${\text{Sr(s) + 2H}}_{\text{2}}\text{O(l)}\stackrel{}{\to }{\text{ Sr(OH)}}_2{\text{(aq) + H}}_{\text{2}}\text{(g)}$

Conclusion

The complete and balanced equation of the given equation is written as:

${\text{Sr(s) + 2H}}_{\text{2}}\text{O(l)}\stackrel{}{\to }{\text{ Sr(OH)}}_2{\text{(aq) + H}}_{\text{2}}\text{(g)}$

Interpretation Introduction

(d)

Interpretation:

The given equation has to be written complete and balanced

Concept Introduction:

Balancing the equation:

• There is a Law for conversion of mass in a chemical reaction i.e., the mass of total amount of the product should be equal to the total mass of the reactants.
• The concept of writing a balanced chemical reaction is depends on conversion of reactants into products.
• First write the reaction from the given information.
• Then count the number of atoms of each element in reactants as well as products.
• Finally obtained values could place it as coefficients of reactants as well as products.
• Loss of electron and loss of Hydrogen in a compound is oxidation - the compound is oxidized.  Gain of electron, gain of Oxygen in a compound is reduction - the compound is reduced.
• Oxidation reduction and reduction reaction occur simultaneously in same reaction.

To Write: The given equation complete and balanced.

Answer to Problem 21.104QP

The complete and balanced equation for the given equation is:

${\text{SrCO}}_{\text{3}}\text{(s) + 2HCl(aq)}\stackrel{}{\to }{\text{ CO}}_2{\text{(g) + H}}_{\text{2}}{\text{O(l) + SrCl}}_{\text{2}}\text{(aq)}$

Explanation of Solution

Given Equation:

${\text{SrCO}}_{\text{3}}\text{(s) + HCl(aq)}\stackrel{}{\to }$

Complete Equation:

A complete equation will have same elements present on both sides of the equation.

The above equation can be completed by writing as follows,

${\text{SrCO}}_{\text{3}}\text{(s) + HCl(aq)}\stackrel{}{\to }{\text{ CO}}_2{\text{(g) + H}}_{\text{2}}{\text{O(l) + SrCl}}_{\text{2}}\text{(aq)}$

Balancing the equation:

A balanced equation will have same elements and same number of atoms of each side of the reaction.

List the atoms of the equation in a table and check for the equal number of atoms present on either side of the reaction.

${\text{SrCO}}_{\text{3}}\text{(s) + HCl(aq)}\stackrel{}{\to }{\text{ CO}}_2{\text{(g) + H}}_{\text{2}}{\text{O(l) + SrCl}}_{\text{2}}\text{(aq)}$

Reactant side	Atom	Product side
1	$\text{Sr}$	1
3	$\text{O}$	3
1	$\text{H}$	2
1	$\text{Cl}$	2
1	$\text{C}$	1

To balance the $\text{Cl and H}$ atoms, multiply $\text{HCl}$ on the reactant side by two.

${\text{SrCO}}_{\text{3}}\text{(s) + 2HCl(aq)}\stackrel{}{\to }{\text{ CO}}_2{\text{(g) + H}}_{\text{2}}{\text{O(l) + SrCl}}_{\text{2}}\text{(aq)}$

Again, list the atoms of the equation in a table and check for the equal number of atoms present on either side of the reaction.

Reactant side	Atom	Product side
1	$\text{Sr}$	1
3	$\text{O}$	3
2	$\text{H}$	2
2	$\text{Cl}$	2
1	$\text{C}$	1

The number of atoms on both sides of the reaction are same. Therefore, the above equation is a balanced one.

Hence, the complete and balanced form of the given equation is written as:

${\text{SrCO}}_{\text{3}}\text{(s) + 2HCl(aq)}\stackrel{}{\to }{\text{ CO}}_2{\text{(g) + H}}_{\text{2}}{\text{O(l) + SrCl}}_{\text{2}}\text{(aq)}$

Conclusion

The complete and balanced equation of the given equation is written as:

${\text{SrCO}}_{\text{3}}\text{(s) + 2HCl(aq)}\stackrel{}{\to }{\text{ CO}}_2{\text{(g) + H}}_{\text{2}}{\text{O(l) + SrCl}}_{\text{2}}\text{(aq)}$

Interpretation Introduction

(e)

Interpretation:

The given equation has to be written complete and balanced

Concept Introduction:

Balancing the equation:

• There is a Law for conversion of mass in a chemical reaction i.e., the mass of total amount of the product should be equal to the total mass of the reactants.
• The concept of writing a balanced chemical reaction is depends on conversion of reactants into products.
• First write the reaction from the given information.
• Then count the number of atoms of each element in reactants as well as products.
• Finally obtained values could place it as coefficients of reactants as well as products.
• Loss of electron and loss of Hydrogen in a compound is oxidation - the compound is oxidized.  Gain of electron, gain of Oxygen in a compound is reduction - the compound is reduced.
• Oxidation reduction and reduction reaction occur simultaneously in same reaction.

To Write: The given equation complete and balanced.

Answer to Problem 21.104QP

The complete and balanced equation for the given equation is:

${\text{Ba(OH)}}_{\text{2}}{\text{(aq) + CO}}_{\text{2}}\text{(aq)}\stackrel{}{\to }{\text{ BaCO}}_3{\text{(s) + H}}_{\text{2}}\text{O(l)}$

Explanation of Solution

Given Equation:

${\text{Ba(OH)}}_{\text{2}}{\text{(aq) + CO}}_{\text{2}}\text{(aq)}\stackrel{}{\to }$

Complete Equation:

A complete equation will have same elements present on both sides of the equation.

The above equation can be completed by writing as follows,

${\text{Ba(OH)}}_{\text{2}}{\text{(aq) + CO}}_{\text{2}}\text{(aq)}\stackrel{}{\to }{\text{ BaCO}}_3{\text{(s) + H}}_{\text{2}}\text{O(l)}$

Balancing the equation:

A balanced equation will have same elements and same number of atoms of each side of the reaction.

List the atoms of the equation in a table and check for the equal number of atoms present on either side of the reaction.

${\text{Ba(OH)}}_{\text{2}}{\text{(aq) + CO}}_{\text{2}}\text{(aq)}\stackrel{}{\to }{\text{ BaCO}}_3{\text{(s) + H}}_{\text{2}}\text{O(l)}$

Reactant side	Atom	Product side
1	$\text{Ba}$	1
4	$\text{O}$	4
2	$\text{H}$	2
1	$\text{C}$	1

The number of atoms on both sides of the reaction are same. Therefore, the above equation is a balanced one.

Hence, the complete and balanced form of the given equation is written as:

${\text{Ba(OH)}}_{\text{2}}{\text{(aq) + CO}}_{\text{2}}\text{(aq)}\stackrel{}{\to }{\text{ BaCO}}_3{\text{(s) + H}}_{\text{2}}\text{O(l)}$

Conclusion

The complete and balanced equation of the given equation is written as:

${\text{Ba(OH)}}_{\text{2}}{\text{(aq) + CO}}_{\text{2}}\text{(aq)}\stackrel{}{\to }{\text{ BaCO}}_3{\text{(s) + H}}_{\text{2}}\text{O(l)}$