Cathodic Protection (Zinc Sacrificial Anode)

Zn → Zn²⁺ + 2e⁻

Overview

A zinc sacrificial anode is electrically connected to a steel structure. Since zinc has a more negative electrode potential (-0.76 V) than iron (-0.44 V), zinc preferentially oxidizes, supplying electrons that keep the steel in its reduced (protected) state. The zinc anode is consumed over time and must be replaced.

Participants

Role	Substance	Coefficient	State
Reactant	Zinc Zn	1	(s)

Everyday Example

Ships' hulls, water heaters, and underground pipelines all use zinc blocks bolted to steel for corrosion protection.

Industrial Importance

Cathodic protection prevents billions of dollars in corrosion damage annually to ships, pipelines, bridges, and offshore platforms.

Properties

Type: Electrochemical
Reversible: No
Energy: Exothermic
ΔH: -147.0 kJ/mol

Related Reactions

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Frequently Asked Questions

What is the equation for Cathodic Protection (Zinc Sacrificial Anode)?

The balanced equation is: Zn → Zn²⁺ + 2e⁻.

What type of reaction is Cathodic Protection (Zinc Sacrificial Anode)?

Cathodic Protection (Zinc Sacrificial Anode) is a electrochemical reaction.

Is Cathodic Protection (Zinc Sacrificial Anode) exothermic or endothermic?

Cathodic Protection (Zinc Sacrificial Anode) is exothermic (releases energy). The enthalpy change (ΔH) is -147.0 kJ/mol.