Final answer:
The correct chemical equation that supports the law of conservation of matter is Option b (CH₄ + 2O₂ → CO₂ + 2H₂O), as it is properly balanced with the same number of atoms of each element on both the reactant and product sides.
Step-by-step explanation:
To determine which chemical equation supports the law of conservation of matter, it is necessary that the number of atoms for each element in the reactants matches the number of atoms for each element in the products. This means the chemical equation must be balanced.
Let's examine each chemical equation given:
- Option a: H₂O → H₂ + O₂. This equation is not balanced because there is one oxygen atom on the product side and two oxygen atoms on the reactant side. It violates the law of conservation of matter.
- Option b: CH₄ + 2O₂ → CO₂ + 2H₂O. This equation is balanced, with one carbon atom, four hydrogen atoms, and four oxygen atoms on both sides. It supports the law of conservation of matter.
- Option c: CO₂ + H₂O → C₆H₁₂O₆ + O₂. Without coefficients, this equation cannot be balanced as written and thus does not support the law of conservation of matter.
- Option d: NaCl + H₂O → NaOH + HCl. This equation appears balanced, but without coefficients, we cannot confirm that it satisfies the conservation of matter for certain.
The correct answer is Option b (CH₄ + 2O₂ → CO₂ + 2H₂O), which is a balanced chemical equation, and thus, illustrates the law of conservation of matter.