For Conservation of mass and balanced chemical equations, which option best supports this Unit 4.3 objective: State that the law of conservation of mass means no atoms are lost or made during a chemical reaction?

The correct option is To show the correct proportions of reactants and products..

The correct option is To show the correct proportions of reactants and products.. To show the correct proportions of reactants and products. is correct because it directly supports the approved learning objective to state that the law of conservation of mass means no atoms are lost or made during 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 conservation of mass 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.