Chapter 17, Problem 38AE

(a)

Interpretation Introduction

Interpretation:

The false part in indicated equation has to be identified.

  ${\text{Cu}}^{+}+{\text{e}}^{-}\to {\text{Cu}}^{2+}$

Concept Introduction:

• In order to balance any redox reaction method used in acidic medium is summarized below.
• In the first step oxidation number of each element is identified.
• The overall reaction is divided into oxidation and reduction held cell based upon changes observed in oxidation states.
• Each side of half-cell equation is balanced except $\text{H}$ and $\text{O}$.  The electrons lost are made equal to electron gained so as to add two half-cells and formulate overall reaction equation.
• In next step $\text{O}$ atoms are balanced by addition water molecule.
• For the acidic medium, excess electrons are neutralized by addition of ${\text{H}}^{+}$ ions to each side.

Oxidation refers to phenomenon of loss of electrons; loss of electropositive $\text{H}$ and gain of electronegative $\text{O}$ and substance oxidized is termed as reducing agent.

Reduction is process that involves gain of electrons, gain of $\text{H}$ or loss of electronegative $\text{O}$ atom and substance reduced is termed as oxidizing agent.

(b)

Interpretation Introduction

Interpretation:

The false part in indicated equation has to be identified.

  ${\text{Pb}}^{2+}+{\text{e}}^{2-}\to \text{Pb}$

Concept Introduction:

Refer to part (a).