Which statement best explains how balanced chemical equations demonstrate the law of conservation of mass?

• A. They show that the total number of atoms of each element is the same on both sides of the equation.
• B. They show that chemical reactions can create or destroy atoms.
• C. They prove that the mass of reactants is always greater than the mass of products.
• D. They indicate that the total number of molecules is always equal on both sides of the equation.

Answer: (A)

Verified step by step guidance

1. Understand the law of conservation of mass, which states that mass cannot be created or destroyed in a chemical reaction.
2. Recognize that a balanced chemical equation has the same number of atoms of each element on both the reactant and product sides.
3. Note that balancing equations ensures the total mass of reactants equals the total mass of products, reflecting the conservation of mass.
4. Identify that the number of molecules may differ on each side, but the total atoms of each element remain constant.
5. Conclude that balanced chemical equations demonstrate the law of conservation of mass by showing equal numbers of atoms for each element on both sides.