Chapter U5.17, Problem 7E

(a)

Interpretation Introduction

Interpretation:The given chemical reaction is redox reaction or not is to be stated. The compound getting oxidized, reduced and the number of electrons transferred is to be determined.

Concept introduction:A chemical reaction in which oxidation and reduction takes place simultaneously is called redox reaction.

Answer to Problem 7E

The given chemical is not a redox reaction.

Explanation of Solution

The given chemical reaction is,

  ${\text{Tl}}_{\text{2}}\text{O}\left(s\right)+2\text{HCl}\left(l\right)\to 2\text{TlCl}\left(aq\right)+{\text{H}}_{\text{2}}\text{O}\left(l\right)$

The oxidation number of $\text{Tl}$ in ${\text{Tl}}_{\text{2}}\text{O}$ and $\text{TlCl}$ is $+1$ . The oxidation number of $\text{H}$ in $\text{HCl}$ and ${\text{H}}_{\text{2}}\text{O}$ is $+1$ . The oxidation number is not getting changed in this reaction. Therefore, the given chemical is not redox reaction.

(b)

Interpretation Introduction

Interpretation:The given chemical reaction is redox reaction or not is to be stated. The compound getting oxidized, reduced and the number of electrons transferred is to be determined.

Concept introduction: A chemical reaction in which oxidation and reduction takes place simultaneously is called redox reaction.

Answer to Problem 7E

The given chemical is not a redox reaction.

Explanation of Solution

The given chemical reaction is,

  $\text{HgS}\left(s\right)+2\text{HCl}\left(aq\right)\to {\text{HgCl}}_2\left(aq\right)+{\text{H}}_{\text{2}}\text{S}\left(aq\right)$

The oxidation number of $\text{Hg}$ in $\text{HgS}$ and ${\text{HgCl}}_2$ is $+2$ . The oxidation number of $\text{H}$ in $\text{HCl}$ and ${\text{H}}_{\text{2}}\text{S}$ is $+1$ . The oxidation number is not getting changed in this reaction. Therefore, the given chemical is not redox reaction.

(c)

Interpretation Introduction

Interpretation:The given chemical reaction is redox reaction or not is to be stated. The compound getting oxidized, reduced and the number of electrons transferred is to be determined.

Concept introduction: A chemical reaction in which oxidation and reduction takes place simultaneously is called redox reaction.

Answer to Problem 7E

The given chemical is not a redox reaction.

Explanation of Solution

The given chemical reaction is,

  ${\text{PbCO}}_3\left(s\right)+2\text{HCl}\left(aq\right)\to {\text{PbCl}}_2\left(aq\right)+{\text{H}}_{\text{2}}{\text{CO}}_3\left(aq\right)$

The oxidation number of $\text{Pb}$ in ${\text{PbCO}}_3$ and ${\text{PbCl}}_2$ is $+2$ . The oxidation number of $\text{H}$ in $\text{HCl}$ and ${\text{H}}_{\text{2}}{\text{CO}}_3$ is $+1$ . The oxidation number is not getting changed in this reaction. Therefore, the given chemical is not redox reaction.

(d)

Interpretation Introduction

Interpretation:The given chemical reaction is redox reaction or not is to be stated. The compound getting oxidized, reduced and the number of electrons transferred is to be determined.

Concept introduction: A chemical reaction in which oxidation and reduction takes place simultaneously is called redox reaction.

Answer to Problem 7E

The given chemical is not a redox reaction.

Explanation of Solution

The given chemical reaction is,

  ${\text{Na}}_{\text{2}}{\text{C}}_2{\text{O}}_4\left(aq\right)+{\text{CaCl}}_2\left(aq\right)\to {\text{CaC}}_2{\text{O}}_4\left(s\right)+2\text{NaCl}\left(aq\right)$

The oxidation number of $\text{Na}$ in ${\text{Na}}_{\text{2}}{\text{C}}_2{\text{O}}_4$ and $\text{NaCl}$ is $+1$ . The oxidation number of $\text{Ca}$ in ${\text{CaCl}}_2$ and ${\text{CaC}}_{\text{2}}{\text{O}}_4$ is $+2$ . The oxidation number is not getting changed in this reaction. Therefore, the given chemical is not redox reaction.

(e)

Interpretation Introduction

Interpretation:The given chemical reaction is redox reaction or not is to be stated. The compound getting oxidized, reduced and the number of electrons transferred is to be determined.

Concept introduction: A chemical reaction in which oxidation and reduction takes place simultaneously is called redox reaction.

Answer to Problem 7E

The given chemical is a redox reaction. The compound getting oxidized and reduced is $\text{Pb}\left(s\right)$ and $\text{HCl}\left(aq\right)$ , respectively. The number of electrons transferred in this redox reaction is $2$ .

Explanation of Solution

The given chemical reaction is,

  $\text{Pb}\left(s\right)+2\text{HCl}\left(aq\right)\to {\text{PbCl}}_2\left(aq\right)+{\text{H}}_{\text{2}}\left(g\right)$

The oxidation number of $\text{Pb}$ in $\text{Pb}\left(s\right)$ and ${\text{PbCl}}_2$ is $0$ and $+2$ , respectively. Hence $\text{Pb}\left(s\right)$ is getting oxidized. The oxidation number of $\text{H}$ in $\text{HCl}$ and ${\text{H}}_{\text{2}}$ is $+1$ and $0$ , respectively. Hence $\text{HCl}\left(aq\right)$ is getting reduced. The number of electrons transferred in this redox reaction is $2$ .

(f)

Interpretation Introduction

Interpretation:The given chemical reaction is redox reaction or not is to be stated. The compound getting oxidized, reduced and the number of electrons transferred is to be determined.

Concept introduction: A chemical reaction in which oxidation and reduction takes place simultaneously is called redox reaction.

Answer to Problem 7E

The given chemical is a redox reaction. The compound getting oxidized and reduced is $\text{As}\left(s\right)$ and $\text{HCl}\left(aq\right)$ , respectively. The number of electrons transferred in this redox reaction is $3$ .

Explanation of Solution

The given chemical reaction is,

  $2\text{As}\left(s\right)+6\text{HCl}\left(aq\right)\to 2{\text{AsCl}}_3\left(aq\right)+3{\text{H}}_{\text{2}}\left(g\right)$

The oxidation number of $\text{As}$ in $\text{As}\left(s\right)$ and ${\text{AsCl}}_3$ is $0$ and $+3$ , respectively. Hence $\text{As}\left(s\right)$ is getting oxidized. The oxidation number of $\text{H}$ in $\text{HCl}$ and ${\text{H}}_{\text{2}}$ is $+1$ and $0$ , respectively. Hence $\text{HCl}\left(aq\right)$ is getting reduced. The number of electrons transferred in this redox reaction is $3$ .