Question

What happens when zinc or iron react with dilute sulphuric acid. Explain your answer by giving a suitable chemical equation. Why does copper not show similar behaviour?

Answer 1

Hint – First write the chemical equation of the reaction of zinc and iron with dilute sulphuric acid. Also, Copper is not used in the displacement reaction as it is present below hydrogen in the activity series, so it cannot displace hydrogen from sulphuric acid.

Complete step-by-step answer:
We have to explain the reaction of zinc or iron with dilute sulphuric acid.
So, let us refer the equation of chemical reaction of zinc and iron with dilute sulphuric acid-
$
  Zn + {H_2}S{O_4} \to ZnS{O_4} + {H_2} \\
  Fe + {H_2}S{O_4} \to FeS{O_4} + {H_2} \\
 $
Now, we can see from the above reaction equation that when zinc or iron reacts with dilute sulphuric acid, a displacement reaction occurs.
Zn and Fe displace the hydrogen from sulphuric acid and form $ZnS{O_4},FeS{O_4}$ respectively on reacting with sulphuric acid.
Hence, Zinc forms $ZnS{O_4}$ on reaction with dilute sulphuric acid and iron forms $FeS{O_4}$ by displacement reaction.
Now, we also have to explain why copper does not show similar behaviour.
Reason – Copper is not used when displacement reaction takes place because it is present below hydrogen in activity series, hence it cannot displace hydrogen from sulphuric acid.

Note – Whenever such types of questions appear, then the first thing to keep in mind is that the elements which are below hydrogen in activity series cannot displace hydrogen and hence cannot show displacement reaction, that’s why copper does not show similar behaviour like zinc and iron when reacting with sulphuric acid.