Question

how can you say that the given fuel is an ideal fuel

Answer 1

High calorific value.
Moderate ignition temperature.
Low moisture content.

Answer 2

“ The organic origin of Natural Gas explains why it is made of hydrocarbons (compounds of hydrogen and carbon). The principle ingredient of NaturalGas is the hydrocarbon compound called methane. In many Natural Gas deposits, methane makes more than 70% of the gas composition. ”