Butane, C₄H₁₀, burns in oxygen to give CO₂ and H₂O accordint to the equation:
2C2H₁₀ (g) + 13O₂ (g) → 8CO₂ (g) + 10H₂O (g)
If the butane concentration is decreasing at a rate of 0.20mol/L⁻¹ s⁻¹. What is the rate at which the oxygen concentration is decreasing?