Which statement best describes the law of conservation of mass?

• A. Mass is neither created nor destroyed in a chemical reaction.
• B. The total volume of reactants equals the total volume of products.
• C. Atoms can be converted into energy during chemical reactions.
• D. Energy is always conserved during physical changes.

Answer: (A)

Verified step by step guidance

1. Understand that the law of conservation of mass states that in a chemical reaction, matter cannot be created or destroyed.
2. Recognize that this means the total mass of the reactants before the reaction must equal the total mass of the products after the reaction.
3. Note that this law focuses specifically on mass, not volume or energy, so statements about volume or energy conservation are not correct descriptions of this law.
4. Recall that atoms are rearranged during chemical reactions but are not converted into energy; thus, mass remains constant.
5. Conclude that the best description of the law of conservation of mass is: 'Mass is neither created nor destroyed in a chemical reaction.'