A student placed an iron nail in a blue copper sulphate solution. After some time, a reddish-brown coating appeared on the nail and the solution turned green. Which is the correct conclusion from this observation?
Answer and explanation
Correct answer: Iron is more reactive than copper and displaces copper from its salt solution.
This is a displacement reaction: \(Fe + CuSO_4 \rightarrow FeSO_4 + Cu\). Iron is more reactive than copper, so it displaces copper from copper sulphate solution. Deposited copper forms the reddish-brown coating on the nail, while the iron(II) sulphate formed makes the solution green. This is not neutralisation, because no acid-base reaction producing water occurs.
Frequently asked questions
What is the correct answer to this question?
Iron is more reactive than copper and displaces copper from its salt solution.
Why is this the correct answer?
This is a displacement reaction: \(Fe + CuSO_4 \rightarrow FeSO_4 + Cu\). Iron is more reactive than copper, so it displaces copper from copper sulphate solution. Deposited copper forms the reddish-brown coating on the nail, while the iron(II) sulphate formed makes the solution green. This is not neutralisation, because no acid-base reaction producing water occurs.
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.
