A physical change occurred. Atoms involved in the reaction lost mass. Precipitates were created in the new solution. Gases were released to the atmosphere.
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Which best explains why the total mass of the product(s) would be less than the total weight of the reactant(s) after a chemical reaction?
Possibilities:
- A physical change occurred.
- Atoms involved in the reaction lost mass.
- Precipitates were created in the new solution.
- Gases were released to the atmosphere.

Gases were released to the atmosphere.