Chapter 19, Problem 72E

Interpretation Introduction

(a)

Interpretation:

The two half-cell reactions for the two electrodes needs to be determined.

Concept introduction:

In an electrochemical cell, there are two electrodes that can be observed.

If oxidation takes place on an electrode, that electrode is called anode. The species in that electrode remove electrons and itself gets oxidized.

If reduction takes place on an electrode, that electrode is called cathode. The species in that electrode absorbs electrons and itself gets reduced.

The electrode potential of cell can be calculated as follows:

$E^0{}_{\text{cell}}=E^0{}_{\text{cathode}} -E^0{}_{\text{anode}}$

Interpretation Introduction

(b)

Interpretation:

Magnitude of the current used in electrolysis should be determined.

Concept introduction:

In an electrochemical cell, chemical change is used to produce electricity. It uses electricity to produce a non-spontaneous reaction.

Electrolysis is the process in which a non-spontaneous reaction is driven by the application of electric energy.

The half-cell reaction with the lowest reduction potential reduces 1^st in electrolysis process.

1 mole of electron = 96485 C

$\begin{array}{l}\text{Charge }\left(C\right)=\text{ current }\left(C/s\right)\times \text{ Time }\left(s\right)\hfill \\ \hfill \\ \text{Number of mole of electrons }=\text{ Current }\left(C/s\right)\times \text{Time }\left(s\right)\times \left(1/96485C\right) \hfill \end{array}$

Interpretation Introduction

(c)

Interpretation:

The gas that collected near the anode shouldbe determined and volume of that gas should be calculated.

Concept introduction:

In an electrochemical cell, there are two electrodes that can be observed.

If oxidation takes place on an electrode, that electrode is called anode. The species in that electrode remove electrons and itself gets oxidized.

If reduction takes place on an electrode, that electrode is called cathode. The species in that electrode absorbs electrons and itself gets reduced.