Here's how to identify an equation that obeys this law:
Look for balanced chemical equations:
A balanced chemical equation has the same number of atoms of each element on both the reactant and product sides. This ensures that no atoms are created or destroyed during the reaction, fulfilling the conservation of mass principle.
Example:
The combustion of methane:
* Unbalanced: CH₄ + O₂ → CO₂ + H₂O
* Balanced: CH₄ + 2O₂ → CO₂ + 2H₂O
In the balanced equation, we have:
* 1 carbon atom on both sides
* 4 hydrogen atoms on both sides
* 4 oxygen atoms on both sides
This demonstrates that the mass of the reactants (methane and oxygen) is equal to the mass of the products (carbon dioxide and water).
Important note: The law of conservation of mass applies only to closed systems, where no matter can enter or leave. In open systems, mass can be lost or gained due to factors like evaporation or combustion.
