Question

Differentiate between combination and decomposition reaction with examples.

Answer 1

The difference between combination and decomposition reactions is given below with examples.

Combination reaction	Decomposition reaction
In a combination reaction, two or more compounds combine to form one compound.	A decomposition reaction can be defined as a chemical reaction in which one reactant breaks down into two or more products.
The general representation of combination reaction is A + B → AB	The general representation of decomposition reaction is A ⇢ B +C
Example- Ferrous chloride is a compound, is reacting with Chlorine which is an element to form Ferric chloride. $\underset{\mathrm{Ferrous}\mathrm{chloride}}{2{\mathrm{FeCl}}_2\left(\mathrm{s}\right)}+\underset{\mathrm{Chlorine}}{{\mathrm{Cl}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Ferric}\mathrm{chloride}}{2{\mathrm{FeCl}}_3\left(\mathrm{s}\right)}$	Example- Silver chloride is decomposing into silver and chlorine gas by the action of sunlight. $\underset{\mathrm{Silver}\mathrm{chloride}}{2\mathrm{AgCl}\left(\mathrm{s}\right)}\stackrel{\mathrm{sunlight}}{\to }2\underset{\mathrm{Silver}}{\mathrm{Ag}\left(\mathrm{s}\right)}+\underset{\mathrm{Chlorine}}{{\mathrm{Cl}}_2\left(\mathrm{g}\right)}$