Practice question

Given: The reaction 2X -> Y has an average rate of formation of Y as 4.0 × 10⁻⁴ mol L^{-1 min^{-1 . What is the rate of disappearance of X in the same units? These values define the system as per NCERT data. Formula: Rate = -1/2 fracΔ[X]Δ t = fracΔ[Y]Δ t. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: fracΔ[Y]Δ t = 4.0 × 10⁻⁴, so -fracΔ[X]Δ t = 2 × 4.0 × 10⁻⁴= 8.0 × 10⁻⁴. Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kg⁻¹ K⁻¹, m/s², 10⁻⁵ are properly used as per NCERT.