Oxidation-reduction (redox) reactions are very important because they help make rust. Rust is mainly iron(III) oxide ($\text{Fe}_2\text{O}_3 \cdot n\text{H}_2\text{O}$), and it affects millions of buildings and vehicles every year.

1. What is the Oxidation Process?

• Rust forms when iron comes into contact with oxygen, especially when there's moisture (water).
• This reaction can be shown like this: $\text{4Fe} + 3\text{O}_2 + 6\text{H}_2\text{O} \rightarrow 4\text{Fe(OH)}_3$

2. Why is This Important?

• Rusting causes around $10\%$ of the total cost of steel produced in the world each year. That’s more than $400 billion$!
• Taking steps to prevent rust can make structures stronger and help them last longer.