Question

how is reactivity series useful in displacement reaction ?

Answer 1

The reactivity series helps us to know the order of the reactivites of the common metals. that means it helps us know which metal is more or less reactive metal than the other
So, in displacement reactions we have to find out about which metal will displace the other metal from it's salt solution.
Hence, the reactivity series is very important for displacement reaction.

Answer 2

It helps us to know that which metal is more reactive and which metal less reactive as we are confused that wich metal is more reactive and we put less reactive metal on the place of more reactive metal

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