Question

Distinguish between the following:

Coal and Natural gas as sources of energy.

Answer 1

Sr. No.	Basis	Coal	Natural Gas
1.	Physical State	It is a solid fossil fuel formed from plant matter.	It is a gaseous fossil fuel composed primarily of methane.
2.	Environmental Impact	Highly polluting; burning it releases large amounts of smoke, carbon dioxide, and sulfur.	The cleanest burning fossil fuel; it produces significantly lower carbon emissions and no smoke.
3.	Residue after Combustion	Leaves behind a substantial amount of solid waste in the form of ash.	Burns completely and leaves absolutely no ash or solid residue behind.
4.	Calorific Value	Has a comparatively lower calorific value (heating efficiency per unit of weight).	Has a very high calorific value, making it an extremely efficient energy source.
5.	Transportation	Bulky and heavy; transporting it requires railways, large trucks, or cargo ships.	Highly convenient to transport continuously over long distances via underground pipelines (or as LNG in specialized ships).
6.	Mode of Occurrence	Found in distinct layers or “seams” sandwiched within sedimentary rock formations.	Found trapped in underground porous rocks, often occurring directly above crude oil deposits.