Practice question

Given: What is the heat released when 15.4 g of butane (C₄H₁₀) burns completely? (Δ H° = -2877.3 kJ/mol, molar mass = 58 g/mol) These values define the system as per NCERT data. Formula: Moles = 15.4 / 58 = 0.2655 mol. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Heat = 0.2655 × 2877.3 = 763.9 kJ. 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.