The document provides instructions for an experiment demonstrating the Law of Conservation of Mass. Students measure the mass of a system containing baking soda in a flask and vinegar in a balloon before and after the vinegar is added, triggering a reaction, and again after popping the balloon. Any changes in mass must be explained by the redistribution of atoms between reactants and products, not by the creation or destruction of atoms.

2. Law of Conservation of Mass

5. Instructions
1. Measure 5 g of baking soda and
put into a flask.
2. Measure 20 mL of vinegar and carefully
pour it into a balloon.
3. Carefully attach the balloon to the top of the flask
without spilling the vinegar into the flask.
4. Place the flask with balloon on a weighing scale and
record the mass of the system.
5. Tip the vinegar from the balloon into the test tube and
record your observations.
6. Measure the mass of the system after the reaction.
7. Pop the balloon and measure the mass again.

6. There are times when mass might
appear to change during a chemical
reaction.
If you experience this during an
experiment, be sure to remember the
Law of Conservation of Mass.
The change in mass must be
accounted for in a way other than
destroying or creating atoms.