For which pair of the fuel gases, calorific value (C.V.) of one fuel is almost double that of the other on volume basis (i.e., kcal/Nm³ ), while the C.V. is same on weight basis (i.e., kcal/kg) ?

• A. F. gas and coke oven gas
• B. Propane and LPG
• C. Sewage gas and gobar gas
• D. Propane and acetylene

Answer: (D)