Question 35 - MCQs from NCERT Exemplar - Chapter 3 Class 10 - Metals and Non-Metals

Which of the following can undergo a chemical reaction?

(A) MgSO ₄ + Fe

(B) ZnSO ₄ + Fe

(C) MgSO ₄ + Pb

(D) CuSO ₄ + Fe

Answer.:

Let's go through the options

Chemical reactions only occur when the element being displaced is less reactive than the one trying to displace it.

We can know the reactivities of the metals here from the reactivity series .

• Between Mg and Fe, since Fe is less reactive than Mg , it cannot displace Mg from its salt solution.
• Between Zn and Fe, since Fe is less reactive than Zn , it cannot  displace Zn from its salt solution.
• Between Mg and Pb, since Pb is less reactive than Mg , it cannot  displace Mg from its salt solution.
• Between Cu and Fe, since Fe is more reactive than Cu , it can displace Cu from its salt solution.

So, the correct answer is (d) CuSO ₄ + Fe