Consider the combustion of methane as shown below:
CH₄ (g) + 2 O₂ (g) →CO₂ (g) + 2 H₂O (g) What is the rate expression for each substance in this equation?

Question

Consider the combustion of methane as shown below: CH₄ (g) + 2 O₂ (g)→CO₂ (g) + 2 H₂O (g) What is the rate expression for each substance in this equation?

Quizplus · Accepted Answer

The rate of reaction is inversely proportional to the stoichiometric coefficients of the reactants and products in the balanced chemical equation. For methane combustion, the coefficients are 1 for CH4, 2 for O2, 1 for CO2, and 2 for H2O. Therefore, the rate of disappearance of CH4 and O2 must be adjusted for their coefficients, leading to the correct expression where the rate of change of O2 is halved (due to its coefficient of 2) and the rate of formation of H2O is also halved for the same reason.

Consider the Combustion of Methane as Shown Below