A chemical reaction takes place when iron dust is added to copper sulphate solution but no reaction takes place when copper dust is added to ferrous sulphate solution, why?
(1) The reaction between copper and ferrous sulphate will not occur the reason is that copper is less reactive than iron. The reaction can be written as
(2) In the reactivity series iron is above it will replace the copper in the copper sulphate compound, so this reaction will occur.
(3) The reverse reaction (if possible) can be written as:
(4) Copper is less reactive than iron as iron carries a major position in the reactivity series. So it will not replace the iron in the compound.No reaction will take place here and the equation should be written:
These reactions are also known as displacement reactions.