1which equation demonstrates the law of conservation of mass?

Every balanced chemical reaction demonstrates the law of conservation of mass where the reactants have the same number of atoms as the products. For example, the production of ammonia gas.
N2 (g) + 3H2 (g) -> 2NH3 (g) you can see that there are two nitrogen atoms and six hydrogen atoms on both sides of the equation.

It starts to rust i think