Metal	Iron (II) sulphate	Copper (II) sulphate	Zinc sulphate	Silver sulphate
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

 

What is the decreasing order in reactivity of the following metals A, B, C, and D?

 

 

 

The decreasing order of reactivity of the above metals is in the order B > A > C > D.
Iron is the most reactive element and metal B displaces it from iron sulfate. Metal A displaces copper from copper sulfate so it can also displace other elements from their sulphate solution except iron so it is the second most reactive metal. Metal C can only displace silver, as silver is an unreactive metal so it comes third in position. Metal D is not capable of displacing any element so it is the least reactive metal.