Chapter 21, Problem 21.128P

(a)

Interpretation Introduction

Interpretation: The movement of electrons needs to be identified if magnesium bars are connected electrically to iron pipes.

Concept Introduction: The movement of electrons in any electrolytic reaction depends on the oxidation and reduction reaction. In oxidation, electrons are released and in reduction, electrons are required. Thus, electrons released in the oxidation of a substance cause reduction of other substances.

(b)

Interpretation Introduction

Interpretation: The average flow of current between Mg and Fe in 8.5 years needs to be estimated.

Concept Introduction: The current flowing in a system is related to the mass and time required for the flow as follows:

  $w=\frac{E{q}_{mass}\times I\times t}{F}$

Here, I is current, t is time, w is mass deposited, $E{q}_{\text{mass}}$ is equivalent mass, and F is Faraday’s constant.