Question

Write the reaction rate expressions for the given reaction in terms of the disappearance of the reactants and the appearance of products. Give the expressions for the disappearance of the reactants first, in the order written in the chemical equation. Then write the expressions for the appearance of the products in the order written in the chemical equation. Write the expressions in order of appearance in the equation in the form ± 1 x × Δ[α] Δt where ± is either a plus or a minus sign, not both, x is an integer, and α is a chemical species. Do not include the state of matter.

4NH₃(g) + 5O₂(g) → 4NO(g) + 6H₂O(g)

Answer 1

The reaction rate expressions for the given equation 4NH3 + 5O2 → 4NO + 6H2O in terms of disappearance of reactants and appearance of products are -1/4 × (Delta[NH3]/Delta t), -1/5 × (Delta[O2]/Delta t), +1/4 × (Delta[NO]/Delta t), and +1/6 × (Delta[H2O]/Delta t), respectively.

Step-by-step explanation:

To write the reaction rate expressions for the given chemical equation 4NH3 + 5O2 → 4NO + 6H2O, one must consider both the disappearance of reactants and the appearance of products. The reaction rate expression based on the concentration changes with time can be written as follows:

• For the disappearance of NH3:
  -1/4 × (Delta[NH3]/Delta t)
• For the disappearance of O2:
  -1/5 × (Delta[O2]/Delta t)
• For the appearance of NO:
  +1/4 × (Delta[NO]/Delta t)
• For the appearance of H2O:
  +1/6 × (Delta[H2O]/Delta t)

The negative sign indicates the rate of disappearance (consumption) of reactants, while the positive sign denotes the rate of appearance (formation) of products. The fractions represent the stoichiometric coefficients that are used to relate the rates of consumption of the reactants and the rates of formation of the products based on the balanced chemical equation. The stoichiometric coefficients are necessary to ensure the rate expressions are consistent with the balanced equation.