Answer:
Law of conservation of mass states that the mass of the system must remain constant over time, as the system's mass cannot change because matter is not created nor destroyed.
A balanced chemical equation provides proof of this law. In a chemical equation, the amount of atoms in the reactant side must be equal with that of the product side. In this equation, the amount of atoms are the same on both sides.
[tex]2H_{2} + O_{2} = 2H_{2} O[/tex]
