Question

What is a balanced chemical equation? Why should the chemical equation be balanced?

Answer 1

Balanced chemical equation: A balanced chemical equation is one in which the number of atoms in all molecules is the same on both sides of the equation.

Example: $$\begin{gathered} 3\mathrm{Fe}\left(\mathrm{s}\right)+4{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)⇢{\mathrm{Fe}}_3{\mathrm{O}}_4+4{\mathrm{H}}_2\left(\mathrm{g}\right) \\ \mathrm{Iron}\mathrm{Water}\mathrm{Iron}(\mathrm{II},\mathrm{III})\mathrm{oxide}\mathrm{Hydrogen} \end{gathered}$$

Chemical equations are balanced by obeying the law of conservation of mass.

1. According to this law, "mass can neither be created nor destroyed in a chemical reaction".
2. Following this law, the mass of all elements or molecules on the reactant side should equal the mass of all elements or molecules on the product side.
3. The law of conservation does not apply to unbalanced chemical equations.

Hence, the chemical equation must be balanced to follow the law of conservation of mass.