For Conservation of mass and balanced chemical equations, which option best supports this Unit 4.3 objective: Explain that the mass of the products equals the mass of the reactants in a chemical reaction?

The correct option is To show the number of atoms of each element in a molecule..

The correct option is To show the number of atoms of each element in a molecule.. To show the number of atoms of each element in a molecule. is correct because it directly supports the approved learning objective to explain that the mass of the products equals the mass of the reactants in a chemical reaction. The reasoning belongs to Conservation of mass and balanced chemical equations within Chemical measurements, conservation of mass and the quantitative interpretation of chemical equations, so it should not be confused with nearby quantitative ideas such as mass, moles, concentration, yield, atom economy, or gas volume unless those are named in the objective. Use the focus term reactant to keep the answer aligned with AQA GCSE Chemistry 8462 Unit 4.3. The other options are weaker because they either use the wrong formula, the wrong unit, a vague relationship, or the wrong quantitative context.