Explanation:
Reactions in which there occurs change in chemical composition of combining atoms or substances is known as a chemical reaction.
Change in chemical composition of the combining atoms arises because they need to gain stability by completely filling their octet.
For example, [tex]2Na + Cl_{2} \rightarrow 2NaCl[/tex]
Sodium has 1 valence electron and chlorine has 7 valence electrons. Hence, sodium will donate its 1 valence electron to chlorine atom. As a result, an ionic bond will be formed due to rearrangement in their electronic configuration.
Thus, we can conclude that chemical reactions are the result of an atom attempting to rearrange its configuration to result in a complete outer shell or have a stable octet.
