Question

According to the Law of Conservation of Mass, how many grams of water [H2O] should be present on the product side?

4NH3 + 5O2 → 4NO + 6H2O
15 g + 65 g = 35 g +

Answer 1

Using the balanced equation, 0.669 moles of NH3 will produce 1.0035 moles of H2O. By multiplying the moles of H2O by its molar mass (18.015 g/mol), we find that 18.06 grams of H2O are produced, demonstrating the Law of Conservation of Mass.

Step-by-step explanation:

According to the Law of Conservation of Mass, the mass of the reactants in a chemical reaction must equal the mass of the products. Given the balanced chemical equation 4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(l), the stoichiometry allows us to calculate how many moles of H2O are produced when a certain amount of NH3 reacts.

If 0.669 moles of NH3 react, the ratio of NH3 to H2O in the balanced equation is 4:6, or 1:1.5. Therefore, when 0.669 moles of NH3 react, 0.669 × 1.5 = 1.0035 moles of H2O are produced. To convert this amount to grams, we use the molar mass of water, which is approximately 18.015 g/mol. Hence, 1.0035 moles × 18.015 g/mol results in 18.06 grams of H2O.