Question

Solutions of copper sulphate, iron sulphate and zinc sulphate are prepared and marked I, II and III respectively. Few pieces of aluminium are added to each solution. After some time a change will be observed in:

• A. I and II
• B. II and III
• C. III and I
• D. All of the above

Answer 1

The correct option is D All of the above

This type of comparison can be done by looking at the position of metals in the reactivity series.

In this series, the metals at the top are more reactive so there will be a displacement reaction.

It is a chemical reaction in which a more reactive element displaces a less reactive element from its compound.

Here we can see that Aluminium is on the top of zinc, iron, and copper,

so it will displace all of them from their salt and it will form a salt of aluminium in the solution.

The reaction between the solutions of copper sulphate, iron sulphate and zinc sulphate and Aluminium are given below:

$I.2Al+3CuS{O}_4\to 3Cu+A{l}_2(S{O}_4{)}_3$

$II.2Al+3FeS{O}_4\to 3Fe+A{l}_2(S{O}_4{)}_3$

$III.2Al+3ZnS{O}_4\to 3Zn+A{l}_2(S{O}_4{)}_3$