Which one of the following fuels has the highest calorific value?A Hydrogen gas B LPG C CNG D Petrol

The fuel with the highest calorific value among the options given is A. Hydrogen gas.

Here's why:

1. Calorific value is the amount of energy produced by the complete combustion of a material or fuel. It is measured in units of energy per amount of material, typically kilograms or liters.

2. Hydrogen gas has the highest calorific value of any fuel. It produces about 142 MJ/kg. This is because hydrogen is the lightest element and it has the highest energy content per unit of weight.

3. LPG (Liquefied Petroleum Gas) has a calorific value of about 46 MJ/kg, CNG (Compressed Natural Gas) has a calorific value of about 55 MJ/kg, and Petrol has a calorific value of about 44 MJ/kg.

4. Therefore, among the options given, Hydrogen gas has the highest calorific value.