1 - Heat generation during electrochemical reactions

Abstract

Many researchers think that electrochemical reactions such as metal dissolution (corrosion) and plating occur at room temperature without any heat generation (exotherm) or endotherm (thermal equilibrium). This is a complete misunderstanding. For example, when an iron plate is immersed in nitric acid, the iron plate dissolves while generating hydrogen gas. At that time, both the iron plate and nitric acid become extremely hot. When plating is performed, the bath temperature increases with time. What cause of the fever at this time? It is because the metal dissolution and the oxidation–reduction reaction of the plating reaction are exothermic phenomena (nonequilibrium). In this chapter, I measure the exotherm and demonstrate that the redox reaction is exothermic. The phenomenon of heat generation by this electrochemical reaction is always relevant when explaining the theory of the formation mechanism of plated film in Chapter 2, Plating, metal corrosion phenomenon in Chapter 3, Metal corrosion, power generation mechanism of a battery in Chapter 4, Batteries, and the formation mechanism of chromate film in Chapter 5, Chromate treatment, since it is always relevant when explaining, it will be explained in this chapter.