Yes, the chemical changes are consistent with the law of conservation of mass. Here's why:

The Law of Conservation of Mass

The law of conservation of mass states that in a closed system, the total mass of the reactants before a chemical reaction must equal the total mass of the products after the reaction.

Analysis

* Reactants:

* Sodium (Na): 12.8 g

* Chlorine (Cl2): 19.6 g

* Total mass of reactants: 12.8 g + 19.6 g = 32.4 g

* Product:

* Sodium Chloride (NaCl): 32.4 g

Conclusion

The total mass of the reactants (32.4 g) is equal to the total mass of the product (32.4 g). This confirms that the chemical reaction adheres to the law of conservation of mass.