During an investigation, a scientist heated 2.76 g of silver carbonate until it decomposed to leave a silver residue. There was 2.16 g of silver residue formed. During this chemical reaction, 0.30g of CO2 and 0.30g of O2 were also produced.

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Does the law of conservation of mass hold true in this case? Use complete sentences to justify your answer based on numerical calculations (evidence).

1 answer

To determine whether the law of conservation of mass holds true in this case, we need to analyze the mass of the reactants and the mass of the products formed during the decomposition of silver carbonate.

  1. Initial Mass of Reactants: The only reactant in this case is silver carbonate. The mass of silver carbonate used is 2.76 g.

  2. Mass of Products: The products of the reaction include silver residue (Ag), carbon dioxide (CO₂), and oxygen (O₂). The masses of these products are as follows:

    • Mass of silver residue = 2.16 g
    • Mass of CO₂ produced = 0.30 g
    • Mass of O₂ produced = 0.30 g

Now, let's calculate the total mass of the products:

\[ \text{Total mass of products} = \text{mass of silver} + \text{mass of CO₂} + \text{mass of O₂} \] \[ \text{Total mass of products} = 2.16 , \text{g} + 0.30 , \text{g} + 0.30 , \text{g} = 2.76 , \text{g} \]

  1. Comparison of Masses:
  • Mass of reactants = 2.76 g (initial mass of silver carbonate)
  • Mass of products = 2.76 g (total mass of silver, CO₂, and O₂)

Since the mass of the reactants (2.76 g) equals the mass of the products (2.76 g), we can conclude that the law of conservation of mass holds true in this case. This principle states that in a closed system, matter cannot be created or destroyed in a chemical reaction; it only transforms from one form to another. Therefore, this experiment corroborates the law of conservation of mass, as the total mass before and after the reaction remains constant.