Which two substances must be present for iron to rust?
Answer and explanation
Correct answer: Oxygen and water (moisture)
Rusting is a slow corrosion process in which iron is oxidised in the presence of both oxygen and water or moisture. The product is hydrated iron(III) oxide, commonly called rust. Therefore, option A is correct. Oxygen alone cannot normally produce rust on dry iron, and moisture alone without an oxygen supply is also insufficient.
Frequently asked questions
What is the correct answer to this question?
Oxygen and water (moisture)
Why is this the correct answer?
Rusting is a slow corrosion process in which iron is oxidised in the presence of both oxygen and water or moisture. The product is hydrated iron(III) oxide, commonly called rust. Therefore, option A is correct. Oxygen alone cannot normally produce rust on dry iron, and moisture alone without an oxygen supply is also insufficient.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Chemical Reactions and Equations.
