The law that the scientist used to predict that the product of the reaction would be 15.9 g of copper sulfate is the law of conservation of matter (mass)
The law of conservation of matter states that matter can neither be created nor destroyed during a chemical reaction but can be transferred from one form to another.
The law above suggest that the total mass of reactants is equal to the total mass of the product i.e
Total mass of reactant = Total mass of product
Considering the question given above, we obtained the following:
Mass of Cu = 12.7 g
Mass of S = 3.2 g
Mass of CuS = 15.9 g
Cu + S —> CuS
Reactant = Cu + S = 12.7 + 3.2 = 15.9 g
Product = CuS = 15.9 g
From the above illustration, we can see that the total mass of the reactants is equal to the total mass of the product.
Therefore, we can conclude that the scientist used the law of conservation of matter to predict the mass of the product.
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