Question

Which of the following can undergo a chemical reaction? Na2SO4 + Cu ZnSO4 + Fe MgSO4 + Al CuSO4 + Fe

Answer 1

which of the following can undergo a chemical reaction ?

1. Na2SO4 + Cu ⇒
2. ZnSO4 + Fe ⇒
3. MgSO4 + Al ⇒
4. CuSO4 + Fe ⇒

solution : we know, a more reactive metal can displace of lower reactive metal from its compound.

copper is less reactive than sodium so, reaction between Na2SO4 and Cu can't happen. i.e., Na2SO4 + Cu ⇒ X (not possible)

Fe is less reactive than Zn. so ZnSO4 + Fe ⇒ X (not possible)

Aluminium is less reactive than Mg. so MgSO4 + Al ⇒ X (not possible)

from activity series of metal, iron is more reactive than copper.

so, iron (Fe) can react with CuSO4. it means, Fe displace Cu from CuSO4 and make FeSO4 and Cu.

i.e., CuSO4 + Fe ⇒FeSO4 + Cu

Therefore only option (4) can undergo chemical reaction.