To determine which chemical equation demonstrates the Law of Conservation of Mass, we need to compare the total mass of the reactants to the total mass of the products for each equation. According to this law, the mass of the reactants should equal the mass of the products in a chemical reaction.
Let's go through each reaction step by step:
1. Reaction: [tex]\(56 \, \text{g} \, \mathrm{Fe} + 16 \, \text{g} \, \mathrm{O_2} \rightarrow 88 \, \text{g} \, \mathrm{FeO}\)[/tex]
- Total mass of reactants: [tex]\(56 \, \text{g} + 16 \, \text{g} = 72 \, \text{g}\)[/tex]
- Total mass of products: [tex]\(88 \, \text{g}\)[/tex]
Since [tex]\(72 \, \text{g} \neq 88 \, \text{g}\)[/tex], this equation does not demonstrate the Law of Conservation of Mass.
2. Reaction: [tex]\(78 \, \text{g} \, \mathrm{K} + 71 \, \text{g} \, \mathrm{Cl_2} \rightarrow 149 \, \text{g} \, \mathrm{KCl}\)[/tex]
- Total mass of reactants: [tex]\(78 \, \text{g} + 71 \, \text{g} = 149 \, \text{g}\)[/tex]
- Total mass of products: [tex]\(149 \, \text{g}\)[/tex]
Since [tex]\(149 \, \text{g} = 149 \, \text{g}\)[/tex], this equation demonstrates the Law of Conservation of Mass.
3. Reaction: [tex]\(23 \, \text{g} \, \mathrm{Na_2CO_3} + 1 \, \text{g} \, \mathrm{H_2O} + 28 \, \text{g} \, \mathrm{CO_2} \rightarrow 84 \, \text{g} \, \mathrm{NaHCO_3}\)[/tex]
- Total mass of reactants: [tex]\(23 \, \text{g} + 1 \, \text{g} + 28 \, \text{g} = 52 \, \text{g}\)[/tex]
- Total mass of products: [tex]\(84 \, \text{g}\)[/tex]
Since [tex]\(52 \, \text{g} \neq 84 \, \text{g}\)[/tex], this equation does not demonstrate the Law of Conservation of Mass.
4. Reaction: [tex]\(55 \, \text{g} \, \mathrm{Mn} + 32 \, \text{g} \, \mathrm{O_2} \rightarrow 85 \, \text{g} \, \mathrm{MnO}\)[/tex]
- Total mass of reactants: [tex]\(55 \, \text{g} + 32 \, \text{g} = 87 \, \text{g}\)[/tex]
- Total mass of products: [tex]\(85 \, \text{g}\)[/tex]
Since [tex]\(87 \, \text{g} \neq 85 \, \text{g}\)[/tex], this equation does not demonstrate the Law of Conservation of Mass.
From the above steps, we can see that the only reaction that satisfies the Law of Conservation of Mass is:
[tex]\[ 78 \, \text{g} \, \mathrm{K} + 71 \, \text{g} \, \mathrm{Cl_2} \rightarrow 149 \, \text{g} \, \mathrm{KCl} \][/tex]
This reaction demonstrates the Law of Conservation of Mass because the total mass of the reactants is equal to the total mass of the products.
