To study a single displacement reaction with the help of iron nails and copper sulphate solution.
Displacement reaction is a chemical reaction in which a more reactive element displaces a less reactive element from its compound. Both metals and non-metals take part in displacement reactions.
Example : Reaction of iron nails with copper sulphate solution.
How is the chemical reactivity of metals linked with their position in the electrochemical series?
Chemical reactivity of metals is linked with their relative positions in the activity series. Certain metals have the capacity to displace some metals from the aqueous solutions of their salts.A metal placed higher in the activity series can displace the metal that occupies a lower position from the aqueous solution of its salt. The displacement reaction is not limited to metals only. Even non-metals can take part in these reactions.
Examples are halogens. The activity series of halogen is F > Cl > Br > I.
Note the point:
An important thing to remember with single displacement reaction is that elements that form cations can only displace cations and elements that form anions can only displace anions.
Classification of single displacement reaction:
In this reaction, one cation replaces another one from its solution. A cation is a positively charged ion or metal. All metal displacement reactions are cation replacement reactions.
Let us demonstrate some examples of cation replacement reactions.
For example :The metals such as potassium, sodium, lithium, etc. react more vigorously with dilute acids forming metal salts and hydrogen gases.
The reaction Zn with dil. H2SO4 is often used in the laboratory for the preparation of hydrogen gas.
If a less reactive metal is added to a salt solution of more reactive metal, nothing will happen.
In this reaction, one anion replaces another one from its solution. An anion is a negatively charged ion or non-metal. For example, more reactive halogen replaces less reactive halogen from its solution.
Here, we will discuss the reaction between iron nails and copper sulphate solution.