Chapter 17, Problem 7PE

(a)

Interpretation Introduction

Interpretation:

Whether below half-reaction represents oxidation or a reduction has to be determined.

  $\text{Na}\to {\text{Na}}^{+}$

Concept Introduction:

A redox reaction is a type of reaction that involves the change in oxidation number of a molecule, atom or ion changes due to transfer of electron from one species to another. A complete reaction involves oxidation and reduction.

Oxidation process represents loss of electrons. Reduction process represents gain of electrons. Oxidation numbers are the part of system that is formed to track electrons in reaction.

(b)

Interpretation Introduction

Interpretation:

Whether below half-reaction represents oxidation or a reduction has to be determined.

  ${\text{C}}_2{\text{O}}_4{}^{2-}\to 2{\text{CO}}_2$

Concept Introduction:

Refer to part (a).

(c)

Interpretation Introduction

Interpretation:

Whether below half-reaction represents oxidation or a reduction has to be determined.

  $2{\text{I}}^{-}\to {\text{I}}_2$

Concept Introduction:

Refer to part (a).

(d)

Interpretation Introduction

Interpretation:

Whether below half-reaction represents oxidation or a reduction has to be determined.

  ${\text{Cr}}_2{\text{O}}_7{}^{2-}+14{\text{H}}^{+}\to 2{\text{Cr}}^{3+}+7{\text{H}}_2\text{O}$

Concept Introduction:

Refer to part (a).