Question

Give an example of a reaction in which a less reactive non-metal is displaced by a more reactive non-metal.

Answer 1

Displacement reaction:-

1. The type of reaction where one atom or a set of atoms is replaced with another atom within the same molecule is called displacement reaction.
2. For example when, Silver nitrate is reacted with Copper, the Copper displaces the Silver from the Silver nitrate solution and forms Copper nitrate solution.
3. This happens because Copper is more reactive than Silver, as Copper lies above Silver in the reactivity series.
4. The balanced reaction is :

$\underset{\mathrm{Copper}}{\mathrm{Cu}\left(\mathrm{s}\right)}+\underset{\mathrm{Silver}\mathrm{nitrate}}{2{\mathrm{AgNO}}_3\left(\mathrm{aq}\right)}\to \underset{\mathrm{Copper}\mathrm{nitrate}}{\mathrm{Cu}{\left({\mathrm{NO}}_3\right)}_2\left(\mathrm{aq}\right)}+\underset{\mathrm{Silver}}{2\mathrm{Ag}\left(\mathrm{s}\right)}$

Reaction between Chlorine$\left(\mathrm{Cl}\right)$ and Potassium bromide$\left(\mathrm{KBr}\right)$:-

1. Displacement reactions are not only for metals, they are for non-metals as well.
2. When Chlorine is treated with Potassium bromide, the reaction undergoes a displacement reaction.
3. The Chlorine here displaces the Bromine from the Potassium bromide solution and forms Potassium chloride$\left(\mathrm{KCl}\right)$.
4. Alongside Potassium chloride, Bromine gas is also produced as a product.
5. This is because Chlorine is more reactive than Bromine, as it lies above Bromine in the reactivity series of non-metals.
6. The balanced reaction is:

$\underset{\mathrm{Chlorine}}{{\mathrm{Cl}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Potassium}\mathrm{bromide}}{2\mathrm{KBr}\left(\mathrm{aq}\right)}\to \underset{\mathrm{Potassium}\mathrm{chloride}}{2\mathrm{KCl}\left(\mathrm{aq}\right)}+\underset{\mathrm{Bromine}\mathrm{gas}}{{\mathrm{Br}}_2\left(\mathrm{g}\right)}$

Therefore, the example of a reaction in which a less reactive non-metal is displaced by a more reactive non-metal is:

$\underset{\mathrm{Chlorine}}{{\mathrm{Cl}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Potassium}\mathrm{bromide}}{2\mathrm{KBr}\left(\mathrm{aq}\right)}\to \underset{\mathrm{Potassium}\mathrm{chloride}}{2\mathrm{KCl}\left(\mathrm{aq}\right)}+\underset{\mathrm{Bromine}\mathrm{gas}}{{\mathrm{Br}}_2\left(\mathrm{g}\right)}$