Q.13: What is the difference between the displacement and double displacement reactions? Write equations for these reactions.
In displacement reaction, one element from its salt is displaced by a more reactive element e.g. in following example, Cu is displaced by Zn from CuSO4 because Zn is more reactive.
CuSO4 + Zn —> ZnSO4 + Cu
In double displacement reaction, exchange of ions takes place between two reactants to form new products.
Na2SO4 + BaCl2 —> BaSO4 + 2NaCl