Question

Samples of four metals A, B, C and D were taken and added to the following solution one by one. The results obtained have been tabulated as follows.

Metal	Iron (II) sulphate	Cooper (II) sulphate	Zinc sulphate	Silver nitrate
A.	No reaction	Displacement
B.	Displacement		No reaction
C.	No reaction	No reaction	No reaction	Displacement
D.	No reaction	No reaction	No reaction	No reaction

Use the Table above to answer the following questions about metals A, B, C and D.

(i) Which is the most reactive metal?

(ii) What would you observe if B is added to a solution of copper (II) sulphate?

(iii) Arrange the metals A, B, C and D in the order of decreasing reactivity.

Answer 1

Explanation

A + FeSO₄ → No reaction, i.e., A is less reactive than iron

A + CuSO₄ → Displacement, i.e., A is more reactive than copper

B + FeSO₄ → Displacement, i.e., B is more reactive than iron

B + ZnSO₄ → No reaction, i.e., B is less reactive than zinc

C + FeSO₄ → No reaction, i.e., C is less reactive than iron

C + CuSO₄ → No reaction, i.e., C is less reactive than copper

C + ZnSO₄ → No reaction, i.e., C is less reactive than zinc

C + AgNO₃ → Displacement, i.e., C is more reactive than silver

D + FeSO₄/CuSO₄/ZnSO₄/AgNO₃ → No reaction, i.e., D is less reactive than iron, copper, zinc, and silver

From the above equations, we obtain:

(i) B is the most reactive metal.

(ii) If B is added to a solution of copper (II) sulphate, then it would displace copper.

B + CuSO₄ → Displacement

(iii) The arrangement of the metals in the order of decreasing reactivity is:
B > A > C > D