In the reaction CuO + H₂ → Cu + H₂O, water is formed. What does this show about hydrogen?
Answer and explanation
Correct answer: Hydrogen is oxidised
Hydrogen combines with oxygen removed from copper(II) oxide and forms water. By the classical definition, gain of oxygen is oxidation, so hydrogen is oxidised and option B is correct. Copper(II) oxide loses oxygen and becomes copper; therefore CuO is reduced. Hydrogen is the reducing agent because it causes CuO to lose oxygen, not the oxidising agent. No precipitate is involved in this reaction.
Frequently asked questions
What is the correct answer to this question?
Hydrogen is oxidised
Why is this the correct answer?
Hydrogen combines with oxygen removed from copper(II) oxide and forms water. By the classical definition, gain of oxygen is oxidation, so hydrogen is oxidised and option B is correct. Copper(II) oxide loses oxygen and becomes copper; therefore CuO is reduced. Hydrogen is the reducing agent because it causes CuO to lose oxygen, not the oxidising agent. No precipitate is involved in this reaction.
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.
