Which of the following fuels has the lowest calorific value ?
A Diesel
B CNG
C Methane
D Coal

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.

An Intiative by Sri Chaitanya

(Unlock A.I Detailed Solution for FREE)

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

The fuel with the lowest calorific value is Coal → Option D.

Diesel: Has a high calorific value of about 45,000 kJ/kg, making it a strong fuel source for vehicles and industries.
CNG (Compressed Natural Gas): Mainly methane, with a calorific value of about 48,000–50,000 kJ/kg, which is quite high.
Methane: Pure methane has a calorific value close to 55,000 kJ/kg, higher than coal, diesel, and petrol.
Coal: Depending on type, coal’s calorific value varies between 15,000–27,000 kJ/kg, which is significantly lower than petrol, diesel, CNG, or methane.
Petrol (not in the given options list but part of question stem): Has a calorific value of around 47,000 kJ/kg, higher than coal.

Thus, coal has the lowest calorific value among the listed fuels.

Watch 3-min video & get full concept clarity