Fri July 06, 2012 By: Tanaya Saha

what is the difference between displacement reaction & double displacement reaction

Expert Reply
Sat July 07, 2012

Displacement reaction:The reaction in which one element displaces another element from its compound is known as displacement reaction. In these reactions, more reactive element displaces less reactive element from its compound.

Example- 2AgNO3 (aq) +Cu   Cu (NO3)2 (aq) + 2Ag (S)

Silver nitrate Copper Copper nitrate Silver

In the above reaction, Silver is replaced by copper because copper is more reactive than silver.




Double displacement reaction: The reaction in which two different atoms or group of atoms (ions) are displaced by other atoms or group of atoms (ions) is known as double displacement reaction.

Example –Na2SO4(aq) + BaCl2 (aq)  BaSO4(s) + 2NaCl(aq)

(Sodium Sulphate) (Barium chloride) (Barium Sulphate) (Sodium Chloride )

Here, SO42- displaces Cl- ions and Cl- ions displace SO42- ions or both ions exchange each other. These reactions occur in ionic compounds.

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