Answer:
combining 2 grams of copper and 4 grams of sulfur to make 6 grams of copper sulfate
Step-by-step explanation:
The Law of Conservation of Mass states that matter cannot be created or destroyed in chemical reactions. It posits that the mass of a substance remains unchanged after undergoing a chemical process.
Therefore, according to the question, the procedure that best demonstrates the law of conservation of mass after the chemistry student conducted different procedures is option D.
This is because, the mass of copper and sulfate did not change but merely combined to form a compound.