A student observed that when an iron nail was placed in a blue copper sulphate solution, the solution gradually turned green and a reddish-brown coating formed on the nail. What type of reaction is this?
Answer and explanation
Correct answer: Displacement reaction
Iron is more reactive than copper, so it displaces copper from copper sulphate solution:
\(\mathrm{Fe + CuSO_4 \rightarrow FeSO_4 + Cu}\).
The \(\mathrm{FeSO_4}\) solution is green, and the reddish-brown coating is copper. This is a displacement reaction because a more reactive metal removes a less reactive metal from its salt solution; it is not a combination reaction, in which reactants form a single product.
Frequently asked questions
What is the correct answer to this question?
Displacement reaction
Why is this the correct answer?
Iron is more reactive than copper, so it displaces copper from copper sulphate solution:
\(\mathrm{Fe + CuSO_4 \rightarrow FeSO_4 + Cu}\).
The \(\mathrm{FeSO_4}\) solution is green, and the reddish-brown coating is copper. This is a displacement reaction because a more reactive metal removes a less reactive metal from its salt solution; it is not a combination reaction, in which reactants form a single product.
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.
