Chapter 11, Problem 43A

(a)

Interpretation Introduction

Interpretation:

The given chemical reaction needs to be balanced and the type of reaction needs to be identified.

Concept Introduction:

In a balanced chemical reaction, there are equal number of atoms of an element in both sides of the reaction arrow. A balanced equation must follow the law of conservation of mass.

Answer to Problem 43A

The balanced equation is:

  $3{\text{Hf(s) + 2N}}_2(g)\to {\text{ Hf}}_3{\text{N}}_4(s)$

The type of reaction is combination reaction.

Explanation of Solution

To balance the chemical equation, the following steps needs to be followed:

Step $1$ : Write a skeleton equation.

Step $2$ : Balance the equation using coefficients in order to make the equation follows law of conservation of mass.

Step $3$ : Check if the number of atoms of each element in reactant side is equal to that of products side.

The given chemical equation is as follows:

  $\text{Hf (}s{\text{) + N}}_2(g)\to {\text{Hf}}_3{\text{N}}_4(s)$

Step $1$ : $\text{Hf (}s{\text{) + N}}_2(g)\to {\text{Hf}}_3{\text{N}}_4(s)$

Step $2$ : $3{\text{Hf(s) + 2N}}_2(g)\to {\text{ Hf}}_3{\text{N}}_4(s)$

Step $3$ : Number of $\text{Hf}$ in reactant side and product side is $3$ .

Number of $\text{N}$ in reactant side and product side is $4$ .

The given reaction is a combination reaction. It is a type of chemical reaction in which reactants combine together to form a single product. So, this chemical equation is also a combination reaction.

(b)

Interpretation Introduction

Interpretation:

The given chemical reaction needs to be balanced and the type of reaction needs to be identified.

Concept Introduction:

In a balanced chemical reaction, there are equal number of atoms of an element in both sides of the reaction arrow. A balanced equation must follow the law of conservation of mass.

Answer to Problem 43A

The balanced chemical equation is as followed:

  $\text{Mg(}s{\text{) + H}}_2{\text{SO}}_4(aq)\to {\text{MgSO}}_4(aq)+H_2(g)$

The type of reaction is single replacement reaction.

Explanation of Solution

To balance the chemical equation, following steps need to be follows:

Step $1$ : Write a skeleton equation.

Step $2$ : Balance the equation using coefficients in order to make the equation follows law of conservation of mass.

Step $3$ : Check if the number of atoms of each element in reactant side is equal to that of products side.

The chemical equation given is:

  $\text{Mg(}s{\text{) + H}}_2{\text{SO}}_4(aq)\to {\text{MgSO}}_4(aq)+H_2(g)$

Step $1$ : $\text{Mg(}s{\text{) + H}}_2{\text{SO}}_4(aq)\to {\text{MgSO}}_4(aq)+H_2(g)$

Step $2$ : $\text{Mg(}s{\text{) + H}}_2{\text{SO}}_4(aq)\to {\text{MgSO}}_4(aq)+H_2(g)$

Step $3$ : Number of $\text{Mg}$ in reactant and product side is $1$ .

Number of $\text{H}$ atoms in reactant and product side is $\text{2}$ .

Number of ${\text{SO}}_4$ atoms in reactant and product side is $1$ .

Single replacement reaction is a type of chemical reaction in which one element replaces the second element in the reaction. Thus, the given chemical equation is a single replacement reaction.

(c)

Interpretation Introduction

Interpretation:

The given chemical reaction needs to be balanced and the type of reaction needs to be identified.

Concept Introduction:

In a balanced chemical reaction, there are equal number of atoms of an element in both sides of the reaction arrow. A balanced equation must follow the law of conservation of mass.

Answer to Problem 43A

The balanced equation is as follows:

  $2{\text{C}}_2{\text{H}}_6(g)+7{\text{O}}_2(g)\to 4{\text{CO}}_2(g)+6{\text{H}}_2\text{O(}g\text{)}$

The type of reaction is combustion reaction.

Explanation of Solution

To balance the chemical equation, following steps need to be follows:

Step $1$ : Write a skeleton equation.

Step $2$ : Balance the equation using coefficients in order to make the equation follows law of conservation of mass.

Step $3$ : Check if the number of atoms of each element in reactant side is equal to that of products side.

The chemical equation given is:

  ${\text{C}}_2{\text{H}}_6\text{(}g{\text{) + O}}_2(g)\to {\text{CO}}_2(g)+H_{2}O(g)$

Step $1$ : ${\text{C}}_2{\text{H}}_6\text{(}g{\text{) + O}}_2(g)\to {\text{CO}}_2(g)+H_{2}O(g)$

Step $2$ : $2{\text{C}}_2{\text{H}}_6(g)+7{\text{O}}_2(g)\to 4{\text{CO}}_2(g)+6{\text{H}}_2\text{O(}g\text{)}$

Step $3$ : Number of $\text{C}$ in reactant and product side is $4$ .

Number of $\text{H}$ atoms in reactant and product side is $\text{12}$ .

Number of O atoms in reactant and product side is $14$ .

Combustion reaction is a chemical reaction in which a compound reacts with oxygen to produce heat and water. Thus, the given chemical equation is a combustion reaction.

(d)

Interpretation Introduction

Interpretation:

The given chemical reaction needs to be balanced and the type of reaction needs to be identified.

Concept Introduction:

In a balanced chemical reaction, there are equal number of atoms of an element in both sides of the reaction arrow. A balanced equation must follow the law of conservation of mass.

Answer to Problem 43A

The balanced equation is as follows:

  ${\text{Pb(NO}}_3{\text{)}}_2(aq)+2\text{NaI}(aq)\to {\text{PbI}}_2(s)+2{\text{NaNO}}_3\text{(}aq\text{)}$

The type of reaction is double displacement reaction.

Explanation of Solution

To balance the chemical equation, following steps need to be follows:

Step $1$ : Write a skeleton equation.

Step $2$ : Balance the equation using coefficients in order to make the equation follows law of conservation of mass.

Step $3$ : Check if the number of atoms of each element in reactant side is equal to that of products side.

The chemical equation given is:

  ${\text{Pb(NO}}_3{\text{)}}_2(aq)+\text{NaI}(aq)\to {\text{PbI}}_2(s)+{\text{NaNO}}_3\text{(}aq\text{)}$

Step $1$ : ${\text{Pb(NO}}_3{\text{)}}_2(aq)+\text{NaI}(aq)\to {\text{PbI}}_2(s)+{\text{NaNO}}_3\text{(}aq\text{)}$

Step $2$ : ${\text{Pb(NO}}_3{\text{)}}_2(aq)+2\text{NaI}(aq)\to {\text{PbI}}_2(s)+2{\text{NaNO}}_3\text{(}aq\text{)}$

Step $3$ : Number of $\text{Pb}$ in reactant and product side is $1$ .

Number of ${\text{NO}}_3$ atoms in reactant and product side is $\text{2}$ .

Number of $\text{Na}$ atoms in reactant and product side is $2$ .

Number of I atoms in reactant and product side is $2$ .

Double displacement reaction is a type of chemical reaction in which positive and negative ions of two aqueous solutions exchange places to form two new compounds. Here, exchange of nitrate and iodide ions take place between lead and sodium thus, the given chemical equation is a double displacement reaction.