The document provides instructions on how to prove the law of conservation of mass using balanced chemical reactions. It explains that you must 1) balance the chemical equation, 2) determine the molar mass of each compound, and 3) show that the total mass of reactants equals the total mass of products. Examples of balanced reactions are provided to demonstrate this process.

1. Law of conservation of mass:
put it all together!

2. How can you prove the law of
conservation of mass using a balanced
chemical reaction???
H2 + O2  H2O

3. Step one: Balance the reaction
___H2 + ___O2  ___H20

4. Step 2: Determine the molar mass of
each compound
2 H2 + O2  2 H2O

5. Step 3: Add up the mass on each side
of the arrow, they should be equal!
2 H2 + O2  2 H2O

6. Prove the Law of conservation of mass
with this reaction…
Fe + H2O  Fe3O4 + H2
Step 1: Balance the equation
Step 2: Calculate the molar masses of each
reactant and each product.
Step 3: Show mass on product side = mass on
reactant side.

7. 1) Al2O3  Al + O2
2) C2H6 + O2  CO2 + H2O
3) Al + Br2  Al Br3
4) Li + H2O  LiOH + H2
5) C3H8 + O2  H2O + CO2
EC) H2SO4 + Fe  Fe2(SO4)3 + H2
Remember to:
1-Balance equation.
2- find molar mass of all compounds.
3- Add up the masses for each side of the reaction.

8. Na + H2O  NaOH + H2
1) Balance the equation.
2) Calculate the molar mass for each compound
in the reaction.
3) Show the law of conservation of mass by
showing the total of mass of the reactants is
equal to the total mass of the products.

9. Na + H2O  NaOH + H2

10. NaCl + F2  NaF + Cl2
1) Balance the equation.
2) Calculate the molar mass for each compound
in the reaction.
3) Show the law of conservation of mass by
showing the total of mass of the reactants is
equal to the total mass of the products.

11. NaCl + F2  NaF + Cl2